Isuzu Owners Maintenance and Repair



  • atfdmikeatfdmike Member Posts: 414
    Hi, I checked for Isuzu technical service bulletins for oil leakage on your year engine and could find none. I believe that on older SOHC Isuzu engines, replacing the spark plug wire was called for in the event of leakage. I don't know if that would apply in your case. It would only make a difference if your spark plug wires also served to seal the valve cover. Might be worth looking at.
  • atfdmikeatfdmike Member Posts: 414
    Hi, found this for your vehicle from Isuzu. If the heater core is leaking into the vehicle, you might not find much evidence on the ground until you have a swampy interior. Seems like you would smell the glycol though or see some evidence of where it is leaking if it is between the engine and firewall and not the heater core.

    1994 Isuzu Truck Rodeo (4WD) V6-3165cc 3.2L SOHC (6VD1)
    Vehicle Level Technical Service Bulletins Customer Interest Heater Core - Coolant Leakage

    Heater Core - Coolant Leakage


    JUNE 2000


    (SUPERSEDES SB00-12-S001)

    NOTE : Shaded information reflects changes from previous service bulletin.


    ^ 1997 and prior Rodeo (UC) models

    ^ All 1995 and prior Pickup (TF) - SIA built models

    Coolant leakage may be present near the heater core area.

    Possible Cause:
    Aluminum-type core may have eroded resulting in a leak

    To correct this condition, install revised (copper) heater core and casing to replace the existing (aluminum) heater core and casing.


    Refer to published procedure in the appropriate Workshop Manual.
  • atfdmikeatfdmike Member Posts: 414
    Well, I don't know who or how you checked the injectors for fire, but the ecm controls the injectors. It seems unlikely that the engine would run if the ecm was bad, but not impossible. More likely,Is there a possibility that the fuel pump or filter are not working/clogged been checked out? The fuel injectors for the DOHC engine only require about 2 V to work, the SOHC is much higher,about 10 V but still very hard to pick up without the proper digital Multimeter (dmm) with a range lock or hold on it.
    Do NOT check resistance on the ECM itself, as it is solid state and damage could result. Good luck
  • joecwelljoecwell Member Posts: 7
    My apologies if this has already been answered before ... I saw the question posted previously but didn't see an answer anywhere.

    I have replaced brake and turn signal bulbs in the back of my Trooper before with no problem ... there are obvious screws that allow the bulb unit (lenses and all) to be pulled away from the vehicle so the bulbs can be unhooked and replaced.

    But the turn signal bulbs in the front of the car seem to be a different story. The plastic lens covers have no visible screws, and the bulbs do not seem to be accessible by hand from the back of the unit by just opening the hood and reaching in (like the headlight bulbs are). I noticed one screw under the hood that looks like it loosens the top of the bulb housing unit, but there is obviously more than thing holdng it in there because it still barely moves when that single screw is taken out.

    I'm usually pretty good at figuring out where the other bolts are, unless of course it is designed so that you have to take out lots of other things before you can even see them. Before I go overboard disassembling the front of my Trooper, can someone tell me the correct way to change the front turn signal bulbs? I'm assuming I must just be missing something obvious since the rear is so simple.

    Thanks in advance -
  • atfdmikeatfdmike Member Posts: 414
    Here is a link and instructions to the picture:

    Disconnect the battery ground cable.
    Remove the screw at the upper portion of the light bracket, and remove the bracket from the fender.
    Remove the front combination light (1).
    Remove the turn signal light socket (3) by turning it counterclockwise.
    Remove the bulb (2) by turning it counterclockwise while pushing it at the same time.
    To install, follow the removal steps in the reverse order.
  • joecwelljoecwell Member Posts: 7
    Thanks much for the directions and picture.

    I apparently had actually started down the correct path, because I had removed the screw on the upper part of the bracket. But the bracket sure seemed to be still in there pretty tight, and I was worried I would crack the plastic if I tried to force it much harder than I already had. Do you know whether there is any trick to popping it out after the screw is removed ... like grabbing onto a certain part or side of the bracket and/or pulling in some specific direction? Like should it be grabbed on the edge in the front of the vehicle and pulled toward the side of the vehicle, or grab the edge on the side of the vehicle and pulled toward the front? Or some other way?

    Or, should it actually just pop out by itself easily after removing the screw, in which case mine might just need a little muscle after such a long time having never been removed?

    Thanks -
  • rick2456rick2456 Member Posts: 320
    I had a 95.5 Rodeo V6 with the same problem. The isuzu fix was to replace the spark plug wires which included a seal to keep oil out of the spark plug well. Does nothing to stop the leak however. Good luck.
  • atfdmikeatfdmike Member Posts: 414
    I would just be guessing, but I think you are on to it if you just work it a little to see if it is just a little sticky. Maybe once it starts loosening you can see more of it. The manual does not give any better explanation. I would think that if you bounced the heel of your hand on the outside lense you might get a feel for how stuck it is....remove the screw first though!! LOL I would guess trying to lift the assembly might dislodge it IF it is just hooked on the bottom to a slot in a tab in the fender.Maybe someone else has your model and will chip in. Good luck.
  • makayemakaye Member Posts: 81
    What you will find is that there is a stud on the back side of the turn signal lamp assy. That stud goes into the inner fender and is held in place with a white plastic ring in a slip arrangement, held in with friction only. Over time, that thing gets pretty stuck. You may be able to use a flashlight to squirt some silicone on the ring and stud to get it out. I ended up using a thin screwdriver with a long handle and splitting the little ring, discarding it. The lamp assy. still fits snug, but after 1/2 a day trying I got frustrated. There is no way to get anything behind the stud to help push it out of the ring. :mad: I even removed the grille and the metal brackets around the headlamp, AND the headlamp trying to get at it. No go. The hole the stud goes through is just fractionally bigger than the plastic ring, so it is not a big deal to me. Nothing wiggles with the upper screw back in place.
    I was even thinking of trying to thread a thin wire around the back of the lamp assy. and pulling it forward, like a sling. However, there is a decorative rubber molding on the side of the assy. that would have been damaged.
    So, I made a "shadetree modification" to the design.
  • joecwelljoecwell Member Posts: 7
    Thanks for the information on the back stud, cuz that now makes sense why it still seems to be in there very firm even with the screw out. Thanks also for the tip on the engineering change :)!

    Obviously Isuzu must have split the workload on the original designs of the front bulb brackets and the rear ones between different engineers :).

    Thanks again to both you and atfdmike for the helpful info.

  • makayemakaye Member Posts: 81
    Suction cup on the face of the lamp assembly?
  • atfdmikeatfdmike Member Posts: 414
    I don't know how you have made out so far, but I looked through Isuzu Technical service bulletins and found one for 1999. You don't specify which motor you have in your Rodeo, but if you think it would help, I can email you next week with the entire bulletin. This is just the subject matter for the TSB I found. It goes in to greater detail in the complete bulletin.
    APRIL 1996

    (Supersedes SB96-01-L001, to include sublet allowance information)


    Trooper (UX) and Rodeo (UC) models equipped with 6VD1 SOHC engine.
  • atfdmikeatfdmike Member Posts: 414
    Hey there! Noticed your shout out and no reply, so Hi back to you, and don't go thinking all Americans are "ugly" or rude. I have a 94 Trooper myself. Best to you.
  • trooper100trooper100 Member Posts: 1
    Hello, I hope that you can help. Last week my TOD check light began flashing, and has not stopped since. I spoke to the dealership and they want me to drop it off for testing and possible repairs. I know that they are going to charge me a lot of money that I don't have to repair it. Have you heard of this problem??? any suggestions
  • atfdmikeatfdmike Member Posts: 414
    I suggest that you try a search in this forum and the trooper forum to see what other owners have found with this problem. Just type TOD or torque on demand in the search window at the top of the page in the forums you wish to search. Supply a little more specific information about your vehicle too, like year, model, engine and transmission type. You should get quicker and more specific information that way. Good luck.
  • smaxwell90smaxwell90 Member Posts: 1
    I have a 1998 Trooper with the 3.5L engine and automatic transmission and about 92,000 miles.

    Yesterday, I noticed that the engine was cranking a little slowly, as if the battery were going dead. While driving, I noticed that my iPod, which was plugged into the cigarette lighter, didn't appear to be charging although the light on the charger was on. Later in the day, I stopped to get gas and the engine wouldn't start. It sounded like it didn't have enough power to crank the engine. I got a jump start and the engine started fine. I drove to the store to get a new battery but it turned out that my battery was fully charged and in good shape. I tried jumpstarting the engine again, to no avail.

    Before I turned off the engine at the battery store, the engine was running fine. I have driven cars when the alternator went out, leading to a drained or dead battery. You had to rev the engine at stop lights to generate enough power to keep it running. That wasn't the case with the Trooper. It seemed to idle and run fine and the voltage meter was showing the normal reading.

    When I try starting the engine I can hear a loud clicking, like the solenoid (starter solenoid?) but so far I haven't been able to find the solenoid.

    I'm assuming this could be a problem with A) the solenoid; B) the starter; C) the alternator or D) a loose connection or wiring problem.

    Any thoughts or suggestions on where to start?

    I don't have a repair manual for this vehicle. I am considering buying one to diagnose and repair this problem. I also ran across an online site/service called AllData offered by AutoZone. It appears to be an online version of the factory-type repair manual used by mechanics. Does anyone have any experience with this service? Am I better off buying the manual or having a year's worth of access to the online manual for about $25?

    Any thoughts, ideas or suggestions would be welcome.

  • atfdmikeatfdmike Member Posts: 414
    This is an excerpt from the professional version of for your year and model vehicle. I am not personally familiar with the version you could access through autozone, but if you can follow basic diagnostic ideas, it could be the way to go. In this case, you could also backtrack the manual to find the connector picture that would also help identify the right terminal. A manual provides similar information, but the search function online in the alldatapro database really helps with ideas when you reach the inevitable impasse. Maybe you can determine if it has this function prior to enrolling. Good luck.

    The operating condition of charging system is indicated by the charge warning lamp. The warning lamp comes on when the starter switch is turned to "ON" position. The charging system operates normally if the lamp goes OFF when the engine starts.
    If the warning lamp shows abnormality or if undercharged or overcharged battery condition is suspected, perform diagnosis by checking the charging system as follows:

    Check visually the belt and wiring connector.
    With the engine stopped, turn the switch to "ON" position and observe the warning lamp. If lamp does not comes ON : Disconnect wiring connector from generator, and ground the terminal "L" on connector side. If lamp comes ON : Repair or replace the generator.
  • millejo1millejo1 Member Posts: 3
    I have the exact same problem. No solution yet though. I believe, but am unsure, that the TOD system uses transmission fluid and that there is a way to checkt he level of fluid for just the TOD. Anyone know about that or how to check and fill it if needed?
  • millejo1millejo1 Member Posts: 3
    I recently replaced the starter on my '99 trooper. I am unsure if it's even remotely related, but quite soon afterwards, my TOD light began to flash slowly, and ocasionally fast. I suspect perhaps the fluid is low but do not know where to check it. Can anyone help please help me with this?
  • atfdmikeatfdmike Member Posts: 414
    Hi, I don't know think there would be a relationship between the two events, but these are directions for performing the fluid check. As you discovered, there is no dipstick. I have posted a picture that the directions refer to at :!v=
    Be very careful when working under a running vehicle. You should chock the wheels to insure it will not move while underneath it. I hope this helps you.

    1999 Isuzu Truck Trooper V6-3.5L
    Vehicle Level Maintenance Fluids Fluid - A/T Testing and Inspection
    Testing and Inspection
    Checking fluid level and condition (color and odor) at regular intervals will provide early diagnosis information about the transmission. This information may be used to correct a condition that, if not detected early, could result in major transmission repairs.

    IMPORTANT.- When new, automatic transmission fluid is red in color. As the vehicle is driven, the transmission fluid will begin to look darker in color. The color may eventually appear light brown.

    A dark brown color with burnt odor may indicate excessive fluid deterioration and signal a need for fluid change.

    When adding or changing fluid, use only DEXRON (R) -III.

    CAUTION: DO NOT OVERFILL. Overfilling will cause foaming, loss of fluid, abnormal shifting and possible damage to the transmission.

    Park the vehicle on level ground and apply the parking brake firmly.
    Check fluid level with engine running at idle. NOTE: Be sure that transmission fluid temperature is below 30 °C (86 °F).
    Move the selector lever through all gear ranges.
    Move the selector lever to "Park".
    Let engine idle for 3 minutes and open the overfill screw (1).
    Add released ( this means proper grade) transmission fluid until it flows out over the overfill screw opening.
    Let engine idle until a fluid temperature between 32 °C (90 °F) and 57 °C (135 °F) is reached, then close the overfill screw (1). Torque: 38 Nm (28 ft. lbs.) NOTE: Check transmission fluid temperature with scan tool. Minimum fluid level 57 °C (135 °F) Maximum fluid level 32 °C (90 °F)
    CAUTION: Do not open overfill screw with engine stopped.

    Immediately after driving at sustained highway speeds.
    In heavy city traffic during hot weather.
    If vehicle is towing a trailer.
    If the vehicle has been operated under these conditions, shut the engine off and allow the vehicle to "cool" for thirty (30) minutes. After the cool down period, restart the vehicle and continue from step 2 above.
  • kirkdckirkdc Member Posts: 2
    I am experiencing a strong vibration in the steering wheel when turning the steering wheel on my 92 Trooper between at speeds between 45 - 60 MPH. The ride is relatively smooth when driving straight ahead. The vibration also goes away at speeds over 65 MPH. At speeds under 45 MPH there are no issues. Does anyone know what can be causing this problem?
  • cptsessocptsesso Member Posts: 116
    Anyone here experience this problem with a newer vehicle?

    I have a 2002 Axiom with 49,900 miles. Sunday, while driving to work, temp gauge shot up to beyond hot. I immediately pulled over and shut it down. Smoke coming from under hood and coolant level was near empty.

    I had the vehicle towed to the dealership where I purchased it and they found a coolant line, which passes under the intake manifold, had ruptured. The line had eroded from the inside out and was full of "gunk" as they called it. They asked if I used the vehicle for towing, which I did not, and then suggested I probably did not follow the required maintenance schedule.

    I have all service records which prove I have done the maintenance, but the 3yr/50k warranty had timed out 6 months before. No problem I thought because at their urging I had purchased an extended warranty through CNA, which I was told would cover everything except normal wear and tear items for 10yr/120k. Wrong. They will not cover this coolant line.

    Now this is going to cost me almost $500 to make this repair and I don't have any idea if the overheating may have damaged the engine further. It starts up and idles perfectly, but who knows what might have have been stressed during the overheat.

    Has anyone ever heard of corrosion forming that severely after only 3.5 years and 49k miles?

    Any thoughts would be appreciated.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    If you didn't flush the coolant at least once in that time, it's possible. But then, does your maintenance schedule require this to be done within 49K? If not, one wonders how they could accuse you of neglect. If it does require it and you didn't do it, well then.......

    Anyway, you're out of warranty so the question is really moot I think, unless you can dig up some kind of recall issued on this problem.

    If you shut the engine off in time, you should be okay. Your quick reaction might have paid off. Hope so.
  • atfdmikeatfdmike Member Posts: 414
    Hi, I checked the Technical Service Bulletins and could find none for coolant other than normal service intervals. In the case of your model, the fluid is required to be replaced at service interval of :

    2002 Isuzu Truck Axiom 2WD V6-3.5L
    Vehicle Level Maintenance Service Intervals Normal Service 30000 MI or 48000 KM
    30000 MI or 48000 KM

    Check fluid level replenish if needed. Check at mileage interval or every 12 months whichever occurs first.

    Brake Fluid
    Check at mileage interval or every 12 months whichever occurs first. Replenish fluid if needed.

    Brakes and Traction Control
    Perform at mileage interval or every 12 months whichever occurs first.

    Fluid - A/T
    Check automatic transmission for leaks.

    Check for fluid leaks at mileage interval or every 12 months whichever occurs first.

    Parking Brake System
    Perform at mileage interval or every 12 months whichever occurs first.

    Steering and Suspension
    Perform at mileage interval or every 12 months whichever occurs first.

    Wheel Bearing
    Front wheel bearings

    Brake Hose/Line (S)
    Inspect the vehicles brake lines and hoses. Perform at mileage interval or every 12 months whichever occurs first.

    Cooling System (S)
    Inspect the cooling system, heater hoses, and connections. Check at mileage interval or every 12 months whichever occurs first.

    Cruise Control
    Inspect the cruise control linkage and hoses. Perform at mileage interval or every 12 months whichever occurs first.

    Exhaust System (B)
    Check at mileage interval or every 12 months whichever occurs first.

    Neutral Safety Switch
    Perform at mileage interval or every 12 months whichever occurs first.

    Steering (S)
    Check for looseness, leaks, or damage. Check at mileage interval or every 12 months whichever occurs first.

    Brake Pedal Assy
    Inspect brake pedal play and adjust if necessary. Perform at mileage interval or every 12 months whichever occurs first.

    Drive Belt
    Perform at mileage interval or every 24 months whichever occurs first.

    Accelerator Pedal
    Lubricate accelerator linkage. Perform at mileage interval or every 6 months whichever occurs first.

    Body and Frame (S)
    Perform at mileage interval or every 6 months whichever occurs first.

    Perform at mileage interval or every 12 months whichever occurs first.

    Throttle Cable/Linkage (S)
    Perform at mileage interval or every 6 months whichever occurs first.

    Air Filter Element (B)

    Coolant (E)

    Engine Oil (E)
    Change at mileage interval or every 12 months whichever occurs first.

    Fluid - Differential (S)

    Oil Filter, Engine (S)
    Change at mileage interval or every 12 months whichever occurs first.

    Power Steering Fluid (S)

    Tires (S)
    Check tires and wheels too. Check at mileage interval or every 12 months whichever occurs first.

    (S) = Service Warranty Requirement
    (E) = Emission Warranty Requirement
    (B) = Both Service and Emission Warranty Requirement

    I noticed that it only says check in the service procedure for each interval, but it is at this milestone that it first says change coolant to meet emission warranty requirements. Maybe this info will help you as you deal with it.
  • atfdmikeatfdmike Member Posts: 414
    I was wondering about your extended warranty. Usually there is a toll free number for the company issuing it, found in the paperwork you received with it. Have you contacted them directly or is it just the shop's decision that the problem is not covered? Might be worth asking the warranty company itself. Also, the intervals for coolant change are every 30,000 by the manual, but does it specify that in your owners manual?Again, it might be worth looking at, and if you had it in for any service at or prior to around 30,000 miles, a good dealer should have brought it to your attention if it needed to be done. Hope your luck gets better.
  • cptsessocptsesso Member Posts: 116
    I had the coolant exchanged at 30k. I can't remember what the manual calls for as I do not have it in front of me right now, but I did have it done, so it was probably called for.

    As far as the ext warranty company, the mech at the dealer said he called them and they denied the claim saying it is not covered.

    I am going to pick it up tomorrow and will have a nice little conversation with the sales manager who said all would be covered except wear and tear items.
  • bsw1bsw1 Member Posts: 6
    Hello Group
    Wow what a great forum to find..
    Hello Group

    I am the proud owner of a 1991 Isuzu Trooper (6cyl). Recently I have smelled gas while driving.Sometimes when i stop i also smell it.It seems to be coming from the rear leaks, and not all the time..i replaced the fuel pump 2 years ago..the smell is quite concerning..
    any suggestions? someone told me it could be a faulty gas cap..could this be a cause?
    he gas smell comes into the cab..also we can smell it near the rear of the truck

  • atfdmikeatfdmike Member Posts: 414
    Hi, I hope you are going to check your fuel system thoroughly. I suppose it is possible that the fuel cap might vent, but it is not supposed to, as to keep hydrocarbons out of the atmosphere. I would be very concerned if you smell gasoline at any time besides fueling up. By way of background, you have a pressurized fuel system from the pump to the injectors. That mean while the engine is running, and for 2 seconds after the key is turned on, the fuel pump is making about 35 to 42 pounds of pressure. If it is leaking into the frame, top of tank, skid plate, etc; you might not find any dripping evidence on the ground, especially if it is a tiny high pressure leak. Once you assure yourself that the integrity of the fuel system is OK, IE: tank itself is not leaking (check inside of fuel tank skid plate if equipped) along with above, then you might inspect the emission system. Follows is the factory manual description that might help you. The six cylinder engine has the same basic components. Good luck and let us know how you make out.


    A closed fuel tank ventilation system is used to prevent evaporative hydrocarbon emissions from escaping the fuel system into the atmosphere. Fuel tank vapors are stored in an activated carbon (charcoal) canister when the vehicle is off and vented to the intake manifold to be consumed when the engine is running.
    Here is a link to a diagram to show what the system looks like under the hood and the fuel tank:!v=!v=
    Check hoses for kinks, cuts, deterioration.
    The ECM controlled canister purge vacuum switching valve (VSV) is in the vacuum line to the purge control valve. Normally closed, the VSV opens when energized by the ECM. During idle or cold operation, the VSV is closed (de-energized), preventing canister purging. The ECM energizes the VSV to permit canister purge only under these conditions:
    Engine at operating temperature.
    Engine must run for a specified length of time.
    Vehicle must be operating above a specified road speed.
    Throttle must be open more than a specified angle.

    1991 Isuzu Truck Trooper II L4-2559cc 2.6L SOHC (4ZE1)
    Vehicle Level Powertrain Management Fuel Delivery and Air Induction Fuel Tank Service Precautions
    Service Precautions

    WARNING: Adhere to the following procedures any time the fuel system is being worked on in order to reduce the risk of fire and personal injury:

    Keep a dry chemical (Class B) fire extinguisher near the work area.
    Place a "CAUTION FLAMMABLE" sign in the work area.
    Work in a well-ventilated area. Do not smoke, and keep sparks and open flames away.
    Wear eye protection.
    Use caution when working near the catalytic converter to prevent the possibility of burns or fire. (The temperatures within the converter can exceed 537 degrees C (1000 degrees F).)
    Relieve the fuel system pressure prior to disconnecting fuel system components.
    Disconnect the negative battery cable except for tests where battery voltage is required.
    Use a suitable container to store or catch fuel.
    Do not replace fuel pipe with fuel hose.
    Plug all disconnected fuel line fittings and hoses.
    After making any fuel system repairs ALWAYS inspect for fuel leaks.
    Replace all pipes with the same pipe and fittings that were removed. Do not reuse "O" rings. Always replace.
    Do not attempt repairs on the fuel system until you have read the instructions and checked the pictures relating to that repair.
    Adhere to all Notices and Cautions.
    NOTE: If available, use system bleed valve (schrader) to relieve pressure.

    NYLON FUEL PIPE CAUTIONS: In order to reduce the risk of fire and personal injury observe the following items:

    Replace all nylon fuel pipes that are nicked, scratched or damaged during installation, do not attempt to repair the sections of the nylon fuel pipes
    Do not hammer directly on the fuel harness body clips when installing new fuel pipes. Damage to the nylon pipes may result in a fuel leak.
    Always cover nylon vapor pipes with a wet towel before using a torch near them. Also, never expose the vehicle to temperatures higher than 115°C (239°F) for more than one hour, or more than 90°C (194°F) for any extended period.
    Apply a few drops of clean engine oil to the male pipe ends before connecting fuel pipe fittings. This will ensure proper reconnection and prevent a possible fuel leak. (During normal operation, the O-rings located in the female connector will swell and may prevent proper reconnection if not lubricated.)
  • bsw1bsw1 Member Posts: 6
    Thank you Mike
  • bsw1bsw1 Member Posts: 6
    My truck does not have fuel has a carb
    The carb is not leaking and the smell is mainly around the rear of the vehicle
    Thanks for the info..i will check out the lines,canister,tank etc
    Thanks again
  • atfdmikeatfdmike Member Posts: 414
    :confuse: Hi, You threw me for a loop, but I think that what you are referring to as a carb is actually a throttle body, which has the fuel injectors built in to it. The main difference for leak purposes would be that carbs operate at lower fuel pressures and store fuel in a bowl. Fuel Injection is 3 to 4 more times pressure and the fuel is delivered directly to the injectors in the Throttle Body, which are controlled by the ECM.
    Your model Rodeo does have a fuel tank shield, so a tank leak might now show right away on the ground. Good luck.
  • hikick1hikick1 Member Posts: 39
    I have the same problem with my 92 rodeo. I will not start thoroughly checking the electric system until monday. I have taken it to three different shops and they "assume" it is my alternator or a bad battery. But all voltage reading are normal. It is not either. I did notice where my battery should spike to about14V while running it stays at 10-12. I believe this is because my idle speed is two low. I will adjust via throttle cable then check readings again. When the ignition is off. it charges itself at 14V. Which means it is pulling on its reserve power since the alternator is off because the vehicle is off? So the question is what the heck is pulling juice with the vehicle off? The only electrical abnormality I have is the heater switch will work with ignition I unplugged it. It still can drain a new battery in a week. New alternator, new starter, new battery, same drainage. Sometimes after the battery has been drained a couple of days, it would do that clicking ticking but no start. If I disconnect the battery completely then reconnect, I can sometimes get a start. Bad relay? Eventually the battery will not take a jump while connected to the car. Is it a grounded connection? I have yet to find out.
  • atfdmikeatfdmike Member Posts: 414
    Does your charge warning indicator light other words, relying on the gauge may not give you a true picture of what is going With the engine not running and the ignition switch in ON, terminal L of the regulator is grounded internally providing ground for the charge warning light and the indicator lights up. With the engine running and the alternator charging, terminal L voltage rises and the indicator goes out. If the alternator fails to charge, terminal L grounds internally providing ground for the charge warning light and the indicator lights up.
    1992 Isuzu Truck Rodeo (2WD) L4-2559cc 2.6L SOHC (4ZE1)
    Vehicle Level Technical Service Bulletins All Technical Service Bulletins Electrical - Inspect Connectors for Various Malfunctions
    Electrical - Inspect Connectors for Various Malfunctions
    Information IB05-04-S005
    Inspection Of All Related Wiring Harness Connections
    When Diagnosing Miscellaneous DTC's, Intermittent
    Driveability Concerns, Hard Start, No Start, Incorrect
    Gauges, Inoperative Air Conditioning Systems, Service
    Engine Soon Lamps Illuminated, 4WD Lamp Illuminated,
    Instrument Panel Gauges Inoperative, Cruise Inoperative
    Affected Vehicles

    All Isuzu Vehicles
    Service Information
    When servicing a vehicle for any type of customer concern, the following steps are imperative. Inspect and ensure the integrity of all related wiring harness connectors. If the wiring harness connectors are not properly put together or engaged before they are locked together, numerous types of intermittent conditions may occur, which may include any of the symptoms listed above and possibly others.
    The first step in any type of electrical diagnosis is a visual and physical inspection of the wiring harness connectors for integrity. Many times, the vehicle may be repaired just by disconnecting and reconnecting the connectors. As with all repairs to wiring harness connectors and terminals, a pull test of the terminals within the connector should be performed. A pull test is performed by inserting the proper size terminal test tool (not a paper clip) into the terminal to determine whether or not the terminal is making good contact, or whether the terminal has been damaged from the prior improper connection or lack of connection.
    NOTE : Most terminals used in current module connectors (ECM, BCM, and the like) are small O~64 mm sq terminals and can be damaged by probing with the wrong tool
    For example, if the Connector C2 of the engine wiring harness to the Powertrain Control Module (PCM) is not properly seated into the PCM:

    ^ The cam lock lever may close improperly.

    ^ The cam lock lever may even snap out of position.

    ^ The vehicle may have an intermittent condition with any one of the components which are controlled or monitored by the PCM.

    THE CAM LOCK LEVER IS DESIGNED TO PULL (OR ASSIST) THE CONNECTOR INTO ITS FINAL POSITION ONCE IT HAS BEEN PRESSED STRAIGHT INTO THE PCM HEADER PAST THE INITIAL DETENT, ALLOWING THE LEVER TO BE MOVED INTO THE LOCKED POSITION. It is not only a retainer but an assist during the connection process. When the wiring harness connector is properly connected to the PCM, a snap will be heard when the connector is in position to be fully seated. The cam lock lever may then be closed. The cam lock lever will then do its designated job as both an assist and ensuring the connector does not come apart due to vibration or other types of conditions found in vehicles as they travel down the highway.

    Remember, if a terminal (metal) or the connector (plastic) is damaged, they should be replaced. DO NOT replace the complete wfring harness assembly. Some harnesses are now on order restriction since most harness damage can be repaired.

    Even though this is generic for all Isuzu, Hope this helps.
  • petegospetegos Member Posts: 4
    Hi, The check engine indicator light in our 2001 TOD Trooper has been on continually (except for 2 days, when I borrowed a diagnostic tool and erased the code) for several months. The code is P0141, which is, "Bank 1 Sensor 2 Circuit Malfunction - Oxygen Sensor Heater Circuit Malfunction". I notice no other symptoms or irregularities. Does anyone know what condition this is describing, if some repair is needed, and if we're damaging the vehicle by continuing to drive it? Thanks.
  • ammodogammodog Member Posts: 2
    My son today Reversed his leaf springs on his 1984 Isuzu trooper to get a "lift" on his truck, Ive heard of doing it before in cars but is this dangerous doing this on a 4x4.

    What are the down sides to this and is it safe?

    Question 2....

    Also today He took the pozzie rear end out of a trooper pup and just put it in his trooper. His drive line is about 1 inch short (drives now but rattles a bit) he says its safe to cut the drive-line and put a pipe in it to extend it to give him one more inch. To me this sounds like an accident waiting to happen, he is 17 and the shop teacher has no clue I don't think what he is working on in class, I will call the teacher tomorrow however id like to get your idea here in OT first so I have some questions to ask...

    he also after this has a loose rattle in the front a noise like I had when I had my 69 Chevy when 2 springs broke and they were dinging around in the break well, his trooper does not have this but sounds bad, I don't even want him to drive it right now...

    Thanks for the help in advance, when it comes to Car mechanics I have not a clue, changing filters or Oil is about my limit....
  • atfdmikeatfdmike Member Posts: 414
    Hi, Generally, this would indicate a bad heater on an oxygen sensor. This will affect emissions and possibly the mileage you get on your vehicle. Generally, changing the O2 sensor will eliminate the fault. There is a fuse for the O2 heaters in the underhood fuse box, I don't think this is it, but no harm to check since the other O2 sensors have not set a fault as well,....have you checked it for continuity? Bank 1 sensor 2 02 sensor is mounted behind the right-hand catalytic converter. This would appear to be the sensor generating the fault. You MUST use an anti seize compound when installing a new sensor, or the sensor will be virtually welded in the nipple after you drive the vehicle without it. An auto parts store should have it. Follows is brief..for me..description of operation of sensors.

    Fuel Control Heated Oxygen Sensors

    The fuel control heated oxygen sensors (Bank 1 HO2S 1 and Bank 2 HO2S 1) are mounted in the exhaust stream where they can monitor the oxygen content of the exhaust gas. The oxygen present in the exhaust gas reacts with the sensor to produce a voltage output. This voltage should constantly fluctuate from approximately 100 mV to 900 mV . The heated oxygen sensor voltage can be monitored with a Tech 2. By monitoring the voltage output of the oxygen sensor, the PCM calculates the pulse width command for the injectors to produce the proper combustion chamber mixture.

    Low HO2S voltage is a lean mixture which will result in a rich command to compensate.
    High HO2S voltage is a rich mixture which will result in a lean command to compensate.
    An open Bank 1 HO2S 1 signal circuit will set a DTC P0134 and the Tech 2 will display a constant voltage between 400 - 500 mV . A constant voltage below 300 mV in the sensor circuit (circuit grounded) will set DTC P0131. A constant voltage above 800 mV in the circuit will set DTC P0132. Faults in the Bank 2 HO2S 1 signal circuit will cause DTC P0154 (open circuit), DTC P0151 (grounded circuit), or DTC P0152 (signal voltage high) to set. A fault in the Bank 1 HO2S 1 heater circuit will cause DTC P0135 to set. A fault in the Bank 2 HO2S 1 heater circuit will cause DTC P0155 to set. The PCM can also detect HO2S response problems. If the response time of an HO2S is determined to be too slow, the PCM will store a DTC that indicates degraded HO2S performance.

    Conditions for Clearing the MIL/DTC
    The PCM will turn the MIL "OFF" on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present.
    A history DTC P0141 will clear after 40 consecutive warm-up cycles have occurred without a fault.
    DTC P0141 can be cleared by using the Tech 2 "Clear Info" function or by disconnecting the PCM battery feed
    Finally, I hope this helps. There are more technical checks that can be performed. If you would like to read them, post again and I will try to supply them. They virtually require you to monitor voltages and probe connectors, which can be a tricky business, and something you may not wish to get in to unless replacing the sensor does not work.
    Best of luck!
  • atfdmikeatfdmike Member Posts: 414
    One guys opinion: Reversing leaf spring on an already high center of gravity vehicle can radically alter the handling characteristics of a vehicle.
    Modifying the driveshaft is not too bad for length, but it must be re-balanced due to the added weight and the alignment checked as well. When the suspension is "exercised" in the real world, the spline could be separated from the spindle of the shaft...dangerous and not a good thing to have happen at speed.
    Obviously, rattles are annoying, and commonly, loose shocks, bad control arm bushings and sway bushings are the leading culprits. Again, any suspension item can significantly affect the driveability of the vehicle. Taken all together, I would personally be leery of driving it until a certified mechanic had looked it over. Again, my opinion only.
  • boxtrooperboxtrooper Member Posts: 843
    If the leaf spring reversal is just to clamp the axle under instead of over the spring, that is done often by kids trying to get a free lift. I think it is less safe than stock. I suggest he get a set of aftermarket leaf springs from OME (Old Man Emu) which are stronger than stock and will improve his ride without compromizing safety even while adding an inch or two of lift. He will need to do a torsion bar adjustment in the front to get the front to come up a little to level the vehicle. Maybe he adjusted the torsion bars too far and the front end hits the upper limiter and makes the noise.
    If it were my kid, I'd suggest going with proper suspension upgrade parts and no body lift (no spacers between body and frame). The OME stuff is quite good and while being as off road ready as any suspension can be, the OME also provides a civilized ride on road with better then stock handling. I have added the OME shocks and matched coil springs to two Troopers 95 & 01, and I have been delighted with both.
    The cost of these parts(~$60 each per wheel)can be low compared to the peace of mind you get(no worry about danger from faulty or inadaquate parts)and the nice ride and handling. The 1984 Trooper will ride better than new and perform off road better than new.
    The 1.9L engine and 4 speed manual transmission (the transmission shifted better than any manual I have ever driven) are a great combination. I put over 200K trouble free miles on my 1984 Trooper. The engine can be rebuilt easily if needed and as long as the body is in good shape this Trooper will be ready for another 200K miles.
    Downside is no airbags in this old Trooper.
    Upside is durability, light weight and huge interior make this a great off road choice.
  • skill124skill124 Member Posts: 5
    2002 LS, dealer just told me the right front CV joint needs replacement, told me cost would be like 500 bucks. Whats a good price for that - obviously should probably go to a regular mechanic I guess.
  • elrodeojuanelrodeojuan Member Posts: 1
    i recently ruined my rear suspension by clippin a pole and i thought that this would be a great time to get a suspension lift on my rodeo. so i was wondering if anyon has any advice on which lift is the best and what things i should go about. thanks allot
  • jgomez123jgomez123 Member Posts: 3
    The other day when I was driving my 2001 Trooper TOD I came up to a stop sign and noticed that the TOD lights were blinking and kept doing so when I started moving forward again. They eventually stopped blinking and then only the rear tires lit up. This problem is only when the vehicle is warmed up. I have noticed that it only happens when I am in a forward moving gear. If I take the vehicle out of one of these gears, the TOD indicator starts blinking the rear tires, then they stay lit. I have been looking around for a Maintenance Manual (Haynes) but nobody seems to have one. This is the second Trooper that I own (first one a 1990), since getting the first one I have been impressed with the vehicle as a whole. Anybody have any ideas?
  • atfdmikeatfdmike Member Posts: 414
    Hi, I am not personally familiar with the TOD system, but the manual says it has a memory if codes are set from it. I hope this info helps. If there are codes, post them and we may be able to provide more info. Good luck.
    2001 Isuzu Truck Trooper LTD 4WD V6-3.5L
    Vehicle Level Brakes and Traction Control Antilock Brakes / Traction Control Systems Testing and Inspection Torque On Demand (TOD) System Description of On-Board Diagnostics Precautions on Fault Diagnosis
    Precautions on Fault Diagnosis
    Replacement of Control Unit
    The control unit itself rarely fails. In most cases, the harnesses have failed (e.q. short-circuit) to cause secondary troubles. Other cases include that the cause has been unknown due to intermittent occurrence of troubles and the troubles are removed accidentally along with replacement of control unit, resulting in misjudgment of cause. Therefore, before replacing the control unit, check the connector joints and whether the unspecified current flows in the control unit due to short-circuit between harnesses.

    Trouble Intermittently Observed
    Troubles intermittently observed are mostly attributable to temporary imperfect connection of harnesses and connectors.
    When such troubles are found, check the associated circuit according to the following procedure.

    Check whether improper connectors are plugged in or connector terminals are completely engaged.
    Check whether the terminals are deformed or damaged. If yes, remove the deformation or damage and connect the terminals securely.
    It is likely that wires in the harness are falsely broken. Therefore, in examination of failed harness circuit, shake the harness for check to such extent that the harness will not be damaged.
    Test Run of Filed TOD Vehicle
    If the TOD indicator lamps experienced faulty operation even once in the past, the failed portion can be identified by use of the procedure "Fault Diagnosis from Trouble Codes" or "Fault Diagnosis from Lighting Status of TOD Indicator Lamps". If the troubles that are only recognized as abnormal phenomena of the vehicle by the driver are observed, conduct the test run in the following procedure to reproduce the faulty phenomena and diagnose the fault for each phenomenon.

    Start the engine, and check that the TOD indicator lamps are turned on for about two seconds for initial check; the CHECK lamp goes off; and the TOD indicator lamps display the specified drive mode. (If the CHECK lamp starts blinking, read the trouble codes and identify the failed portion. )
    While keeping the vehicle standstill, operate the 4WD switch and shift the transfer lever to change the modes: 2H mode; TOD mode; 4L mode; TOD mode; 2H mode. Check that the TOD indicator lamps correctly display the status whenever the mode is changed. If the transition status is displayed during the shift operation, run the vehicle a little to complete shifting.
    Slowly start the vehicle in the TOD mode, and add the power to accelerate to at least 40 km/h (25 mph) and maintain the speed for about two minutes. Apply the brake to completely stop the vehicle. Repeat this test pattern at least three times.
    Turn the steering to the right end (or left end) in the TOD mode, and slowly start the vehicle and make a circle five times. Next, conduct the same test in the 2H mode.
    Slowly start the vehicle in the TOD mode, and accelerate to at least 40 km/h (25 mph) . Keep the established speed, carefully change the mode in the sequence "TOD mode; 2H mode; TOD mode" while checking that the shift is complete in each mode change. After the test, apply the brake to completely stop the vehicle.
    Slowly start the vehicle in the TOD mode, and accelerate to at least 40 km/h (25 mph) . Apply the brake strongly so that the ABS works, and completely stop the vehicle.
    Slowly start the vehicle in the 4L mode, and accelerate to at least 20 km/h (12 mph) . Apply the brake to completely stop the vehicle. If the CHECK lamp starts blinking during the test run, read the trouble codes and give appropriate maintenance according to the fault diagnostic procedure. If the TOD indicator lamps are lit abnormally during the run, check the lighting condition and give appropriate maintenance according to the fault diagnostic procedure. Even if the phenomena are not observed, try to reproduce the abnormal state reported by the customer to the possible extent.
    Post-Repair Check
    As long as the starter is not turned off, the TOD indicator lamps continue blinking even after the failed control unit is repaired. Therefore, upon completion of repair, be sure to turn off the starter switch once and then turn on it to conduct the test run sequence specified in steps 1 through 6 above and check that the TOD indicator lamps no longer show any faulty status.

    TOD Indicator Control
    The TOD indicator on the instrument panel informs the driver of the current working status of the transfer unit. The information consists of two items: the drive mode (2H, TOD, 4L, transition) and the torque split status of the TOD (torque distribution level). The indicator can display occasional errors and corresponding error codes.
    To check for codes stored:
    The control unit has a function of self-diagnosis. If a trouble occurs in the course of system start-up, the control unit blinks the CHECK lamp and saves the trouble code.

    Note: If an intermittent fault occurs, the control unit stops blinking upon removal of the fault. The trouble code is saved to the control unit.

    Indication Method of Trouble Code

    Short-circuit terminal 8 of the self-diagnostic connector to GND to display the trouble code on the CHECK lamp.
    If no trouble codes exist, code "12" is displayed continuously.

    If trouble codes exist, code "12" is displayed three times, and the trouble codes, starting from the smaller code number, are displayed three times respectively.

    Here is a link to the aldl connector pin locations.!v=

    Good luck.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Thanks for the helpful post Mike and for supporting the forums.

  • jgomez123jgomez123 Member Posts: 3
    Okay I checked the codes and this is what I found. The first code is 14 and the second code is 24. I am not sure what they belong too. Can anyone provide assistance. I also noticed today that a better discription of the problem is: Whenever I am below 13 mph the TOD lights up all four wheels SOLID then when I begin to pick up speed the lights start to flash. After about 20 mph the TOD flashes 2L and after a couple of flashes (3 or 4) 2L stays on solid. The weird part is that the Check light is not coming on at all.

    Thanks for the help!
  • atfdmikeatfdmike Member Posts: 414
    Hi again, found this:

    2001 Isuzu Truck Trooper LTD 4WD V6-3.5L
    Vehicle Level Brakes and Traction Control Antilock Brakes / Traction Control Systems Testing and Inspection Antilock Brake System Trouble Code Diagnostic Procedures By Diagnostic Trouble Code (DTC) Number DTC 14 - B-2 EHCU Abnormality

    DTC 14 - B-2 EHCU Abnormality

    By Diagnostic Trouble Code (DTC) Number!v=

    2001 Isuzu Truck Trooper LTD 4WD V6-3.5L
    Vehicle Level Brakes and Traction Control Antilock Brakes / Traction Control Systems Testing and Inspection Antilock Brake System Trouble Code Diagnostic Procedures By Diagnostic Trouble Code (DTC) Number DTC 24 - B7 Transfer Monitor

    DTC 24 - B7 Transfer Monitor

    By Diagnostic Trouble Code (DTC) Number!v=!v=

    Okay, I found these, hope they help. also, just from experience, I know that your brake light switch is an integral part of the system and is monitored by the powertrain control module. You might check to see if it is adjusted correctly, if it is telling the tod module the brakes are on, it will effect the engagement speeds of the tod significantly. Just a tip that will at least eliminate one possible source of problems, particularly if it is intermittent.The TOD unit is under the passenger seat, might want to check the connector on that. Also, it monitors a speed sensor for the front driveshaft and another on the rear. Those connectors are on the transfer case near the the respective output shaft to the propeller shafts.
    To me, it seems as though your TOD ECU is seeing some differences in speed from the front to rear, and applying torque to balance. If you want info on the speed sensors, Post again and I will dig deeper.
    Remember to disconnect the battery cable if you are going to disconnect and reconnect any connectors. I think these are pretty easy things to check and then go from there. Good luck.
  • jgomez123jgomez123 Member Posts: 3
    I understood all of that, but what does EHCU stand for and where is it located?
  • tidestertidester Member Posts: 10,059
    EHCU = ElectroHydraulic Control Unit

    I'm sure one of the owners will be able to tell you what it does and where to find it.

    tidester, host
  • pacheacopacheaco Member Posts: 4
    I had the exact same thing happen, starter on friday, TOD flashing the next day. Did you get the check flashing to stop?
  • atfdmikeatfdmike Member Posts: 414
    The ehcu is your antilock brake controller. I don't think that this is where your problem lies as long as you are not getting fault codes for the brake system. It does monitor wheel rotation, and I don't know how or if that information is used by the vehicle other than for stopping. The diagnosis chart just has you taking it out of the loop so to speak for a voltage check on one pin. Again, not a bad idea to carefully disconnect and inspect the connector, cleaning with contact cleaner if necessary.
    Electronic Hydraulic Control Unit (EHCU)
    The EHCU consists of ABS control circuits, fault detector, and a fail-safe. It drives the hydraulic unit according to the signal from each sensor, canceling ABS to return to normal braking when a malfunction has occurred in the ABS.
    The EHCU has a self-diagnosing function which can indicate faulty circuits during diagnosis.
    The EHCU is mounted on the engine compartment front right side. It consists of a Motor, Plunger Pump, Solenoid Valves and Check Valve.
    On the outside, the relay box containing a motor relay and a valve relay is installed.

    Solenoid Valves: Reduces or holds the caliper fluid pressure for each front disc brake or both rear disc brakes according to the signal sent from the EHCU.
    Reservoir: Temporarily holds the brake fluid that returns from the front and rear disc brake caliper so that pressure of front disc brake caliper can be reduced smoothly.
    Plunger Pump: Feeds the brake fluid held in the reservoir to the master cylinder.
    Motor: Drives the pump according to the signal from EHCU.
    Check Valve: Controls the brake fluid flow.
    Hope this helps.
  • eric138109eric138109 Member Posts: 1
    I’ve been good at changing the oil regularly but that's about it. Should I get the timing belt changed and the water pump at the same time? Are the troopers timing belts prone to breaking? What else should I get done? So far it runs great. Thanks in advance for your help!
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