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Chevrolet/Geo Metro



  • zaken1zaken1 Posts: 556
    Your message sounds like one I replied to some time ago. Anyway, here are my takes on this issue. Right now, my 1990 5 speed Metro has a dark brown, dry coating on the inside of the pipe. It turns black in the winter months, when I only do short trips. This happens when the ambient air temperature stays below about 55 degrees Fahrenheit. At those times, my gas mileage in rural non freeway driving drops to around 40mpg. In the summertime, the rural short trip mileage goes up to about 47, and it reaches the mid 50s on freeway trips.

    There are several areas which could make the pipe turn black (which indicates an excessively rich fuel mixture.) One is if the stock 195 degree coolant thermostat has been removed, or has been replaced with one having a colder specification. Similarly, if either the EFI's coolant temperature sensor or the intake air temperature sensor has drifted out of calibration or has developed a resistive connection, it will cause excessive mixture richness.

    The mixture will also go rich if either of the mufflers have been removed, or if they have been replaced with non factory parts. Installing a non standard ignition coil can also create an excessively rich mixture.

    If there are deposits in the fuel injector, or on intake valves; they also can create a rich fuel mixture. The most effective product for removing deposits from those two areas is an exclusive chemical formula called Techroline, which is made by Standard Oil of California. It comes in a black bottle, and is sold nationwide at Wal Mart, Checker, Shucks, Kragen, and Murray auto stores. It is also sold by Standard stations and Chevron dealers.

    Two other things that can create an excessively rich mixture are using an unsuitable brand of spark plug (I've had best results with Autolites, and with Bosch Fusion {although the Bosch Fusions cost about $10 each}), or having a throttle position sensor which is out of adjustment. If your TPS is adjustable, mark the curent position, and try setting it slightly counterclockwise. If you go too far, it will cause a hesitation under moderate acceleration. Your exhaust pipe will tell you when you get it right.

  • I have a 94' Metro 2dr hatchback (Canadian built) that I replaced the engine with a Japanese engine bought off ebay. I can't get spark to the plugs. I had the ignition control module tested and it tested bad. So, Ijust bought a new one for it and still nothing! The parts store I bought the module from said they didn't have anything in the computer for Canadian cars. However, the U.S.module looked exaclty like my Canadian module. So, I went ahead and paid the $90 for it hoping it would work. Wrong. Will this module work or not, or what else could the lack of spark be from? I need to get this thing back on the road quickly. Thanks.
  • zaken1zaken1 Posts: 556
    First of all, it is important not to confuse the country where the car was built, with the country where it was designed to operate. The earlier Metros sold in America were built in Japan, but they were nevertheless designed to meet U.S. specs. They were very different from the cars intended for domestic use in Japan. The same goes for the later model Metros, after production was shifted to Canada. There were two different cars built there; one intended for sale and use in Canada, and the other intended for sale and use in the U.S The emission label under the hood should reveal whether or not your car was designed to meet U.S. regulations. Since all U.S. model Metros of that era were built in Canada, the fact that it was built in Canada doesn't mean it is not a U.S. model. And that bit of information can save lots of confusion at the parts store.

    One unlikely thing I discovered about my Metro is that if I connect a jumper wire from the battery to the coil, in order to bypass any possible resistance in the wiring or the ignition switch; it cuts off the spark from the coil (even though the coil is getting full battery voltage). It appears this is intended as an anti-theft device. So, if you're not using the standard wiring to run the car's electrical system; this could be the reason you have no spark. And since you made new battery cables; did you include the auxiliary ground lead in addition to the usual battery negative cable, I mean the one that goes from the battery negative terminal to the bolt in the inner fender well???

    And then there is the infamous ignition disabling feature built into the seat belt system of Metros of that era. If a seat weight sensor either malfunctions, or detects any weight in one of the seats; the seat belt for that seat MUST be fastened; or the car will not start.

    If the fuel pump does not run, there may be a problem with the fuses in the fuse box under the hood, or possibly with a power relay. The fuel pump normally runs for about 3 seconds when the key is first turned on. After that, it runs as often as required by engine demands.

    This may sound obvious, but it has baffled many people: If the timing belt on your replacement engine has broken or come off, it will cause the distributor shaft to stop rotating. And then the coil will not produce any sparks.
  • Thank you for the response Zaken. What would be a good way to identify my Metro as a car built to operate in the US? I can't find an emissions sticker anywhere under the hood. I haven't made a jumper wire for the coil and I did make a new secondary ground wire to the fender. The old one was very corroded. Could there be any other grounds I'm not finding or that need to be cleaned? One of the first things I did when I got the new engine is to change the timing belt. So, I'm good there. I still can't hear the fuel pump when I turn the key. I have checked the fuses and they all seem to be good. I may have the relay checked to see if it's working. I will take the back seat out and see if the pump is getting power. I am at a real loss here. Thanks for the help. Could use some more though.
  • mljwiremljwire Posts: 7
    You can quickly check your fuel pump relay by swapping it with another one that is the same number like I believe your head light relay. They are the same and should be in the same box under the hood. At least they are on my 95. I got home from the store by doing this. Other than that I suggest you take Zaken's advice.
  • zaken1zaken1 Posts: 556
    You can find out whether your car is a U.S. model from the VIN. That is the number on the plate on your dashboard, on the driver's side, by the windshield. If you give that number to the parts department at a Chevrolet dealership, they should be able to tell you if you have a U.S. model. If you can't get a satisfactory answer from the dealership, I would try calling a larger dealership, finding a more highly motivated employee, or contacting the regional customer service center for General Motors. Another possibility is to contact the Department of Motor Vehicles in your state, and give them the VIN.

    Sounds like you did a professional quality job on the battery cables! The fuel pump probably has its own dedicated ground wire, which goes to a point located near the pump. I have seen that connection on other brands of cars become corroded enough to stop the pump. So by all means unbolt it and clean the terminals. I doubt you can access the pump from under the rear seat. You'll probably have to do it from underneath the car. It doesn't require a hoist. I just remove the left rear tire, and support the body on a jack stand, to gain easier access. But it might even be possible to do it without removing the tire.

    Regarding the 'no spark' condition; it might be useful to see if there is any spark coming from the coil, rather than checking at the plugs. It also would be useful to go through the fuse box in the engine compartment, and see if you can light a test light from the terminals for the fuel pump fuse (at least; I personally would check every fuse and circuit in the whole box) There are lots of points in and around that box which are vulnerable to corrosion.

    And see if all the usual electrical accessories appear to be functioning normally: the headlights, taillights, brake lights, directional signals, heater blower fan, radio, horn, windshield wipers, instrument panel lights, and the 'check engine' light. If there is a pattern of failed items, it might be illuminating.

  • zaken1zaken1 Posts: 556
    A few more thoughts came to mind. No offense intended here; but even though you just replaced the timing belt, have you taken off the distributor cap and looked to see that the rotor spins while the engine is cranking, just to prove that everything is still solidly connected???

    There is another part called an ignition pick up unit, which if it were defective could be causing this problem. But rather than throwing another hundred bucks at the problem, I think it is a better idea to methodically go through the steps that were previously mentioned, and eliminate all the other possibilities we can think of.

    There is a parts source called Rock Auto, which has an online catalog that includes photo images. I looked up your model Metro there, and found several different types of ignition modules. One of them was for Canadian vehicles, and the others were not. It was very difficult for me to tell the difference between the appearance of the parts; but my computer has display problems, and I have not personally seen your module. You might find it helpful to go to their website, and see if anything can be gleaned. Clicking on the blue icon in a listing will bring up the image.

  • zaken1zaken1 Posts: 556
    I just thought of an easier way to determine if this is a U.S. model. Open the driver's side door, and look at the body panel just below the door latch striker. There should be a plate there, which lists the place and date of manufacture. If that plate contains a statement about the vehicle meeting Federal specifications; then it is a U.S. model. If the plate refers to Canadian specifications, then it is a Canadian model. And if there is no plate, then we have an ongoing problem.

    If you can find a serial number on the distributor, the parts department at a dealership should be able to determine from that number whether this is a U.S. or Canadian model; but it the distributor has previously been replaced, then there still would be a mystery.

  • Thank you so much for the advice guys! I will try the headlight relay since I know they work. I did watch to see if the distributer rotor was turning to make sure the belt was still on. No offense taken ;) . That was one of the first things I did. I learned a long time ago to check the little things that would be obvious like that. It helps. :D A buddy of mine has a voltmeter that I could borrow this week. I'll check every fuse in the engine compartment. As for the battery cables, I am very picky and neat when it comes to that sort of thing. I rewired my 69' Olds 442 from bumper to bumper and made sure everything was neat and professional. Soldered and heat shrunk every connection. :shades: This Metro is new to me because it has more electronics to it. So I'm more confused as to what the problem is. I know it has to be something simple. I'm staying positive. Thanks again guys and I'll try the advice you gave. May have more questions though. LOL!
  • I just went to the Rock Auto website. I must have the Metro XFI 61ci. L3 TBI model becuase they list the very same ignition module as mine in the XFI catagory. It has the same numbers on it and everything (J121). However, I just bought one from a parts store here. Oh well, I'll see if it will work. I also checked the sticker on the inside of the driver's side door just below the striker. It reads
    Date 11/93
    This vehicle conforms to all applicable US Federal Motor Vehicle safety, bumper, and theft prevention standards in effect on the date of manufacture shown above.
    VIN # 2C1MR2462R6728129"
    So, I beieve this car was built in Canada but was intended to be operated in the US. Am I right? I also found the ECM (Engine Control Module) on their website and thought I'd see what mine has. They look the same but, I will call them tomorrow because the numbers on mine don't quite match the ones they list. I just want to make sure they are the same in case I need a new computer. Is there any way to test it? Can a parts store or a dealership do that? They cost just over $300 so I want to make sure mine is defective before I buy one.
  • zaken1zaken1 Posts: 556
    You are correct in concluding that you have a U.S. model. But the news that it is an XFI is a surprise. I don't doubt that, but it complicates the situation. XFIs were relatively rare. They were designed to give the highest possible fuel economy. To achieve that, the engine was designed with one less piston ring than the standard engine (for lower friction) and the camshaft had a shorter duration and lower lift. This moved the power curve down to a lower RPM, but it also made less peak power than the standard engine. Those differences were small enough that it wouldn't be a bother to most drivers; but they did require the computer to be calibrated differently. The throttle body also had slightly different (leaner) calibrations, and the spark advance curve was different.

    So, once you get it running; a standard engine with XFI tuning will not run quite like it was intended to. I have an XFI throttle body on my standard Metro, and it has taken a bit of work to get the mixture where it belongs, and to keep the check engine light from protesting. But I now prefer the way it runs.

    If you get it running, and there is a problem with the computer, the check engine light will come on and stay on. That light is supposed to briefly light when you first turn the key, but it should go out when the engine starts. If there is a computer problem, the computer will generate a trouble code, which will cause the check engine light to flash a coded sequence when the key is turned on (before cranking the starter). The sequence can be read and then the explanation can be looked up in a chart. This information is in the service manual. If the engine runs, and the check engine light stays off, then the computer is OK (assuming the check engine light comes on momentarily when the key is first turned on).

    Parts stores are not equipped to test computers. Dealerships can, but they charge a lot to do so, and sometimes the results are misleading. I've seen trouble codes which said one thing, when the problem was something else. Not for the faint hearted, or those who are short of money. In that kind of work, it would be preferable to work with a dealership who was liberal and customer friendly about adjusting their charges to keep things fair; rather than one which charged for everything they did, whether it worked or not.

    But don't forget the ignition pick up unit. If it is bad, you definitely will not get a spark.

    Also, it is not a good idea to use an ohmmeter to test fuses. I've seen too many misleading results. A self powered continuity test light is a much more appropriate tool for that purpose. Connecting a 12 volt light bulb in series with the fuse and the vehicle battery will also work comparably; providing the bulb does not draw more current than the rating of the fuse (a bulb with a rating of between 5watts and 25 watts is preferable). And that same light bulb is the absolute best tool for checking the fuse box to see if each of the fuse sockets can supply enough current to light the bulb; when the other end of the bulb filament is grounded.

  • The reason I think it's an XFI is because Rock Auto has a picture of the same exact ignition control module (or "ignitor"as they call it) as mine and it's listed under "XFI". That and the fact that it has a throttle body are the only things I'm going by. The other "ignitor" picture they have is of a standard Metro and it's different. Would Geo make an XFI with an auto trans if it was designed to get the most mpg out of it? Doesn't make sense to me but, I know some people don't like manual transmissions. That may be why they made an auto trans option. I figured I would have some trouble when I bought the other engine off ebay since it was labled as a carburated engine and mine has a throttle body. I may have to ask what all you had to do to yours to get it running right. I just need to get it running! :mad: I'll try some of the things you mentioned and if that doesn't work then I'll go ahead and buy a new dist. pickup. Thanks again!
  • zaken1zaken1 Posts: 556
    All Geo Metro engines had throttle body fuel injection. Metros were never made with carburetors. The 3 cylinder Chevy Sprint, which was the preceding model to the Geo Metro, and was also designed and produced by Suzuki (although GM sold them in the U.S. under the Chevy and Geo name) had a carburetor, except fuel injection was used on the turbo model, and on the standard engine in 1988, the last year of its model run. Anyway, my point is that the throttle body looks sort of like a carburetor, which leads many people to mistake it for one. So I believe the engine you bought may have been mislabeled as "carbureted."

    I don't believe they made XFIs with automatics, although I'm not absolutely sure. The automatic transmission equipped standard Metros got about TEN miles per gallon less than the manuals. That was the worst possible combination on that car.

    XFIs usually had all black rear bumpers, while standards and LSIs had a strip on the top edge of the bumper which was white. XFIs also had a decal reading "XFI" above the right tail light.

    But now I need to know: Does your car have an automatic transmission???

  • zaken1zaken1 Posts: 556
    I wanted to mention that there is another option to sort out this problem. There is a brand of repair manual called Mitchell, which is used by shops which specialize in fuel injection and electrical work. They publish a huge, thick, book each model year, which covers each individual brand of car in complete detail. This is the Mother Lode of diagnostic information. For example, I was working on a 1993 Acura Integra the other day, which also had a 'no spark' condition that could not be fixed by replacing the usual components. So I drove to the Mountain View, CA public library, which has in their reference section a full set of Mitchell manuals for every recent model year. I looked through the 1993 Acura Integra information, and ended up photocopying 75 pages of wiring diagrams, logic trees, computer trouble codes, and self diagnostic procedures. Included in that information was the Acura part number of a factory diagnostic tool called a 'break-out box.' This part is normally found only at dealerships, but can be ordered through the dealership parts department, by using the part number listed in the Mitchell manual. It is a special electrical adapter, which plugs in to the computer, and to the wiring harness plug which normally goes into the computer. It has several rows of numbered terminals, perhaps 60 pins in all, to which you can connect a digital voltmeter and read the voltage on each individual wire in the vehicle harness. This custom made tool makes it possible to troubleshoot the entire wiring harness, without cutting into it. AND IT COST ONLY ABOUT $8 FROM THE DEALERSHIP. This is what it takes to sort out a 'no spark' problem when the fault is not in the usual components.

    So if you have access to a digital voltmeter, and are willing to put the time into it, this is the way to save the massive labor charges which you'd have to pay at a dealership or specialist shop, to fix this problem. Of course, you might be able to fix it by replacing every major part in the ignition system, but since there has been lots of corrosion in the wiring harness, I think there is a substantial chance that the problem is NOT a defective component, but is instead a fault in the wiring. But, without being to 'see' the overall condition of the electrical system; you would just be playing Russian Roulette.

    Very few libraries have a full set of Mitchell Manuals, but some can order them, or can tell you where they can be found. It might also be possible that a friendly local electrical and fuel injection shop will let you copy pages from a Mitchell Manual that they have. Or you might be able to buy one online. I don't know whether there is a break-out box available for Geo Metros, but I do know that the information you need to fix this problem is in that manual. And if you do take it on; the experience and confidence you thereby gain will benefit you for the rest of your life.

  • tr3250tr3250 Posts: 1
    My inner wheel arches are completely rusted and need replaced. Where can i get reasonably priced sheet metal parts? I'm OEM is out of this world.
  • zaken1zaken1 Posts: 556
    Find a local auto wrecker who preferably has access to the nationwide hot-line. If they don't have a Metro with the parts you need, they can put a call out on the parts locator, and have them shipped in from any other yard that has them.
  • Joel,
    Yes, that is another option that I may have to pursue. To answer your question, yes, I do have an automatic trans. It also has all black bumpers but, no XFI badges to speak of. The car was wrecked then repainted so, that may be why. The only reason I think I have an XFI is because on Rock Auto's website they have a picture of an XFI ignition control module or "ignitor" and it looks just like mine with the #'s J121 on it. The standard module doesn't look like mine. I think I'll take my vin # to the dealership and see what they can come up with as far as what model I have. A few posts ago you mentioned seeing if I have spark coming from the coil. How do I do that? I know the obvious way is to hold the coil wire close to a ground and crank the engine but, I don't want to fry any other electrical parts! So, if there is another way I'd like to know. Thanks again!
  • zaken1zaken1 Posts: 556
    The all black bumper, plus the ignition control module pretty clearly cinch the issue that it is an XFI. I don't think any further investigation is needed there. So they did make XFIs with automatics!! The reason I asked about the transmission type is that the throttle position switch is different on 5 speed cars than on automatics.

    A safe method of checking the spark at the coil would be to borrow one of the plug wires from the distributor, along with a clean spark plug. Attach the plug wire directly to the coil, and plug the other end of the wire onto a spark plug. Clamp the metal body of the spark plug so that it is held firmly against a grounded metal object. Turn on the key and crank the engine, while watching the plug electrodes. If the coil is producing a spark, you'll see it jump across the plug gap.
  • Hi, I have a 1996 metro 1.3l, auto with the same timing problem. I bought the Haynes manual, but it didn't help! My car has the 6 pin plug, but it only has 4 places to jump, only it doesn't tell you what hole is what! Did you ever get an answer to your question? Do you know where I can find some help, I've looked everywhere I can think of. Thanks, Tom
  • zaken1zaken1 Posts: 556
    The 1996 Mitchell electrical systems manual which covers servicing of your model car should have the information you need. These manuals are usually found only in professional shops. They go into far more detail than Haynes, Chilton, and the other "do it yourself" manuals which are commonly available. Because Mitchell manuals are written for commercial shops, each edition covers many brands and models of vehicle. So they are much larger and thicker than other types of manuals; and cost accordingly more. Some libraries have them in their reference department, and that would be the best way to access one. But because of the cost, and the fact that new editions are published for each new model year; most libraries cannot afford to buy them. The Mountain View, California library has a complete set. You may be able to get your local library to request one, or maybe you could pay someone to go to a library that has one, and photocopy the information. Or perhaps a local fuel injection specialist shop will let you look at theirs.

  • I feel kind of foolish. I found the diagram of which pins to jump by looking at a decal under the hood! If you don't have that decal, it's like this:

    ------------------------------------------------Firewall------------------------- - - ------


    no wire> X O O

    O-O O
    jump these two terminals

    I hope that's clear.
    Steve B.
  • If you want to know if you have an xfi check your serial number. Regular metros had a MR in the begining and xfi was MS. They never made the xfi with an automatic as the xfi was all about high gas mileage and you aren't going to get in the high 50's with out a 5 spd. Ken.
  • Mine's an MR and a 5 spd 1.0 liter.

    My exhaust pipe is fluffy black with a black ring around the outside.

    Looking for at least 50 mpg,
    Steve B.
  • An XFi was a Geo Metro built for economy. It was the most economical car available in the States all the time that it was available.
    two rings per cylinder, special economy cam, no passenger mirror, no air conditioning unless installed by dealer, a low final drive albeit higher than the 4 cyl sohc.
    A little less hp BUT sooo economical.
    You can still get that FE by dropping in a XFi cam and swapping your final drive gear and pinion. I did it and don't regret it one bit. Augment tire pressure also. Advance timing (at the distributor level) by at least 6 degrees, it should get rid of soot.
    I wish you success. Check
  • thebeavthebeav Posts: 1

    My new metro runs great and starts fine after it warms up. But on a cold start, it won't or has trouble turning over, the timing belt squeals on rev and it putters out and dies on idle and when engaging 1st gear. Any thoughts on where I might start to fix this/these problems?

    Also, anyone have thoughts on the original service manual versus the Chilton Paper Repair Manual as to which one is better?

  • mljwiremljwire Posts: 7
    Hello zaken1
    Mljwire here; (Les)
    I have done your suggested testing on the rough idle and loss of gas mileage on my 95 Geo. I am not sure about the issues I found with the TPS and I now believe the rough idle is actual slow idle as described in the idle air valve check.

    1995 Geo Metro
    Manual 5 speed
    VIN# 2C1MR2267S6785502
    Manufactured in Canada.
    Complies to US.
    Throttle Body 13400 50G11

    1. Throttle position sensor. (Denso 13420-50G00, 198500 3090) It is adjustable. When checking I do not see the switching terminals as you mentioned and as the diagram and set up procedure shows in the Haynes Repair Manual for 1985 to 2001. I marked the TPS position and removed it and rechecked it by rotating the coupling fully CW & CCW. I do not see the switch. I do see the resistor and the wiper. The feller gauge between the stop-screw could not be set. I went to Advanced Auto and compared a new TPS of the same manufacture and part# and it tested exactly the same. I have included the resistance readings of the TPS. Please let me know if I am doing something wrong.
    Pins CCW CW
    1-2 Inf. Inf.
    1-3 .004ohm 3.31ohm
    1-4 3.65ohm 3.65ohm
    2-3 Inf. Inf.
    2-4 Iinf. Inf.
    3-4 3.67ohm .49ohm

    2. Spark Plugs. New in 2007. I started with Champion RN12YC. I checked the Champion website and confirms the correct application. The plugs are nice and tan, no carbon or oil and gap measured good. I changed them to Autolite AP63 and set the gap to .041”.

    3. Cap and Rotor. New in 2007. I inspected the cap and rotor and found no carbon tracking. I cleaned the slight oxidation on the conductor pins in the cap. The leading edge of the rotor looks like new. I noticed what looks to be hairline cracks in the top of the cap plastic at the point where the three conductor pins mount. The cracks migrating toward the rotor contactor. I was going to replace it but when I inspected the cap from Advanced Auto I noticed the exact same condition. I plan to get a different brand.

    4. MAP Sensor. I checked the electrical connections for corrosion and did not see any. I checked the electrical connector for bad wires/connections, ok. I replaced the vacuum line to the TB and checked the conection spigot, ok. I checked the voltage of the MAP sensor and from the
    OBK to GBK wires
    The voltage measured 3.66v with the key on and not running.
    @ Idle 2.13v
    Reeve engine 1.6v

    5. Idle Air control Valve. The Haynes manual say the idle air control valve is pre 94 models. I have a 95 which has idle speed control motor I tested the motor by placing 6v on the ISC motor terminals and the motor extended and retracted. I do not see the ISC motor on the wiring diagram. I found an idle up from the A/C control amplifier on the heating and A/C diagram but I have not located the module yet. There is also a 15a IG fuse that I also did not locate. I checked all the 15a fuses under the dash, they are ok. Under the passenger side dash there are two boxes a metal case which I believe is the ECM and a black plastic box, is this the PCM?
    I believe this could be a good possibility because I noticed that the idle speed does not change when I turn the A/C on and off or when I step on the brake. At this point I believe that my rough idle may actual be low RPM. I tried to do a check of the RPM but it is rudimentary at best as I used my old tach/dwell meter set on 4cyl and calculating about ¾ of the value which I am sure is inaccurate but I was hoping it would be close.
    RPM (0.75 of actual reading on 4cyl tach)
    Cold 600rpm
    Hot 350rpm sounds extremely slow and it looks slow.

    6. Dirty Fuel. Changed fuel filter annually. Changed it again. The rough idle seems to have started a 1 ½ years ago progressively getting worse. I have used the Techroline cleaner.

    7. EGR Valve. I removed and cleaned the EGR valve again. It was still pretty clean. I checked all diaphragms and vacuum lines for leaks and operation. Last time I went through and did all of the operational checks in the manual. This time I confirmed that the diaphragm was moving when revving the engine.

    8. Timing. I have owned this car since 3K miles and have never adjusted the timing. The timing is specified under the hood as 5deg at idle.850rpm. I checked it by jumping the test terminal as specified and it is at 5deg BTDC at idle although the manual says to check it at various RPM I do not have the correct tach so this check is also rudimentary but at idle it is correct.

    9. PVC valve. Replaced.

    I also;
    Changed the air cleaner.
    Checked and repaired all vacuum lines.
    Replaced Timing belt.

    Sorry about the length. I want you to have details. I am thinking I need to figure out this idle speed control motor control circuit because that is supposed to increase the idle with the A/C on and I believe it used to increase when the brake was depressed. The idle does not increase for any conditions that I see.
  • zaken1zaken1 Posts: 556
    Hi Les,
    Thanks for all the detail. It was very helpful. But I'll be brief here, for simplicity's sake.

    1> It sounds like either TPS pins 1-3, or 3-4 are the ones that switch. I'd use whichever pair's reading changes abruptly between the low and high figures when the throttle is opened a little above idle, with the housing set about midway in its travel. Then lock the housing in the position where the switching takes place when the throttle linkage opens .018" from fully closed throttle.

    2> I'd stay with the Autolite plugs, as you have them set, and would definitely search around for a distributor cap without manufacturing cracks (try a NAPA parts store).

    3> It sounds like the idle air control circuit is not working. I suppose it may just require more extreme conditions to activate it; but I expect it is inoperative. I can't help you with the repair procedure, but there should be an explanation in a 1995 Mitchell electrical systems manual (a huge, thick book that covers all brands of cars). The trick is to find one. Local library reference desk would be a start. A good fuel injection repair specialist will probably also have one, but may or may not cooperate with your need for information.

    4> I wouldn't try this until all of the above items are resolved, (PARTICULARLY THE IDLE SPEED CONTROL MECHANISM) but sometimes the idle air bypass screw in the throttle body has to be reset. This cross head brass screw is hidden inside a boss, on the driver's side of the throttle body, near the rear edge of the casting, perhaps halfway up between the throttle body mounting flange and the air filter housing. There is a black rubber plug covering the screw when they are new. Turning the screw in (clockwise) enriches the mixture, and usually slows down the idle. Loosening the screw leans the mixture and speeds up the idle. There will be a range of adjustment over which the idle quality is pretty good, and there should be a sharp peak of smoothness within that range. But the throttle position must be set right before you can find that spot, and that means either fixing the idle speed control, or resetting the throttle stop to a further open position.

    5> I assume you've checked the compression pressure. It should be very close to 195psi (which is a lot more than it is on most cars). Anything less than 180 fails.

    Everything else you mentioned sounds good.

    Best Wishes,
  • If you have not fixed problem try Helm Manuals. You can get specific ones for mechanical,electrical,body. They are very detailed step by step manuals.
  • mljwiremljwire Posts: 7
    Thank you for you time. I am working on getting a factory manual and I will try your suggestion.
  • mljwiremljwire Posts: 7
    Thanks I will look for them.
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