Are you an EV owner who has received a shockingly high quote for repairs? A reporter would like to speak with you; please reach out to [email protected] by Friday, May 26 for more details.

Chevrolet Blazer Engine and Performance Problems



  • tommyj2tommyj2 Member Posts: 2
    97 GMC Jimmy with a V6 Vortec, motor was bought from Advance and has around 40000 miles. I didn't put the motor in, it was already installed when I bought it. Hope someone can help me with this miss problem, I will try to explain it the best that I can. First off, new plugs, new plug wires, new coil pack, fuel filter and air filter. Catalytic converter has been removed. No Check engine light is on. The vehicle starts perfect and idles perfect, but when you go up a hill it sometimes has a bad hesitation like you are letting off the fuel back and forth, give it more gas and it quits. Then sometimes on flat ground at 55 mph it does the same thing. Sometimes I can pull into a parking lot at 3 mph or at an idle and the motor has a violent stutter to it. That has only happened twice. So can anyone enlighten me on this subject??
  • sealteam8sealteam8 Member Posts: 11
    Actuall it is not the motor. my moms blazer is doing the same thing and it is a factory gm motor. I am trying to track down that problem this week if i figure it out i will post another message to this problem.
  • bowtie468443bowtie468443 Member Posts: 2
    In some older GM transmissions there was a problem with electronic solenoids sticking and not allowing the trans. to downshift out of lockup. This may be part of your problem
  • bowtie468443bowtie468443 Member Posts: 2
    It has all new tune-up items and clean battery connections. It runs good once it starts but it cranks longer than it ever did .Appx. 130k milage. Inoticed some leakage around the front of the intake. ?????????????????It stalled on me last night and didn't want to idle at first ????????????
  • mcainmcain Member Posts: 1
    my dash lights dont work and it wont kick out of 4whl drive will someone please help i dont know what it is
  • nightauditor2nightauditor2 Member Posts: 1
    97 chevy blazer started fine but after filling tank it would not start it cranks strong and every thing was working except the idiot light . i had the key in the on postion while i was waiting for help to arrive and the lights came on and it started just fine. turned it off and the same thing happened after about five min. the next time i turned it off the lights did not come on and it will not start
  • sealteam8sealteam8 Member Posts: 11
    It could be a number of things. Like a fuel filter or fuel pump. or ignition coil. Check to see if you have the three basic needs. fuel, spark, and of course you will have exhaust... The spark should be bright blue. not orange! and fuel pressure should be around 62 pounds with the key on and engine off. and 60 pounds with the key on and the engine running. let me know!
  • kalani1kalani1 Member Posts: 1
    My car wont start. It turns over but thats it. Not the battery as I just replaced it and like I said it turns over. I was snowed in for 10 days and 2 days ago tried to get out-my car was fine and it started but ice and snow was too thick so all it did was spin the tires but I think it affected the engine because e tried for about an hour and only got 4ft!!!!!!
    The car was missing alot about 2 weeks ago and suddenly stopped. I have been told it is the fuel filter or pump??? I am new here and will have to get it towed in the morning but also dont want to get taken advantage of. Any ideas??
  • uniqorn2009uniqorn2009 Member Posts: 3
    In March, I had to change my radiator. It's been running fine until a couple of weeks ago. I parked my blazer and notice water running from under the car. It was coming out just in front of the oil pan. It didn't overheat or anything. I check the fluid and noticed that it wasn't any antifreeze which I purchase and gave to the shop but water. Also it look like stop leak was still in the radiator. I figured that the stop leak was in the motor from the bad radiators leak before I bought the vehical. But I can't find the leak. I can smell it when I drive for awhile and the temp goes just to the 200 degree range but doesn't overheat and now my check engine light is on. There isn't any water in the oil but I did notice water in the exhaust and it was 91 degrees today. Is there anywhere else it could be leaking at?
  • jlflemmonsjlflemmons Member Posts: 2,242
    Could be a water pump leaking, or possibly the intake manifold (a fairly common problem on these engines). If the water pump, you should be able to see water coming out around the shaft. I have been told that with the intake manifold you will find antifreeze in the intake valleys.

    What code has been set? Autozone will check for you.
  • duntovduntov Member Posts: 133
    It is likely the water pump leaking. The water pump has a hole in the casting under the impeller shaft which will leak if a water pump bearing seal fails. That indicates that the wtaer pump needs to be replaced.

    Another more common source of a leak is the thermostat housing to intake manifold gasket. Sometimes they leak a little after they have been replaced until the gasket swells and seals. Especially if the gasket was installed wihout any Permatex High Tack sealer or it was tightened incorrectly or not tightened enough. Many car owners or shop technicians will not tighten those enough after the thermostat has been replaced and the two thermostat housing bolts will need to be snugged up a little to stop a coolant leak. The aluminum thermostat housings are easy to break if they are overtightened. I wish shop technicians were as cautious with oil pan drain plugs.

    Other common sources of coolant leaks from the front ot the engine are:
    1.) Upper radiator hose to thermostat housing connection.
    2.) Lower radiator hose to water pump connection.
    3.) Heater hose connections to the water pump and intake manifold. .
  • uniqorn2009uniqorn2009 Member Posts: 3
    I'll try to see if it's the intake manifold. Autozone stopped checking codes for you
    Thanks for your help :)
  • uniqorn2009uniqorn2009 Member Posts: 3
    the motor is so tight I can't hardly see anything in there. I was thinking maybe it's the engines drain plug that has worked itself loose.

    Thanks but it more than likely a intake manifold problem :)
  • jlflemmonsjlflemmons Member Posts: 2,242
    2001 4.3L engine does not use a thermostat housing gasket. The thermostat itself has a heavy rubber seal that compresses between the housing and the intake manifold and uses no sealer.

    My bets are still on the water pump.
  • jlflemmonsjlflemmons Member Posts: 2,242
    You might try reaching around to the underside of the water pump and see if you get antifreeze on your hand. I would definitely check that before going after the intake manifold.
  • djo611djo611 Member Posts: 4
    I have heard that you should only use dex-cool in the 4.3 engines, yet some mechanics suggest flushing the system and using a 50/50 mix of atifreeze because of gasket eating problems with dex-cool. Is this true?
  • duntovduntov Member Posts: 133
    There was a class action law suit pending against GM concernng people who used Dex-Cool anti-freeze which allegedly ruined their engines. Sadowski/Bertino vs General Motors Corp.

    The class action suit has settled and the suit is closed. The claims were affected by the GM Chapter 11 bankruptcy. ( )

    Why risk using Dex-Cool when the green stuff is a tried and true antifreeze when used as instructed?
  • jlflemmonsjlflemmons Member Posts: 2,242
    "Why risk using Dex-Cool when the green stuff is a tried and true antifreeze when as instructed?"

    Because if you don't get every bit of that Dex-Cool out of the system, you will have problems. Like gasket issues and blocked cooling passages.

    The big issue with Dex-Cool isn't so much the product, as the change interval that GM published. No way do you leave this stuff unchanged for 5 years 100K miles. I have not come across any issues with 60K changes. The 4.3L intake manifold gasket issue is not coolant related, but an issue with the proper torque of the intake manifold and it's flexing/distortion over time. Not all engines are affected (I have two such engines, one with over 90K and no issue) but some have failed in less than 60K miles, most around 70-80K.

    I agree that the standard ethylene glycol antifreeze is good, and has been for years. As long as it is changed at least every 30K or 24 months, it will provide good service. What some folks don't realize is that the antifreeze properties are not the issue, it is the anti-corrosive chemical breakdown that causes problems. Nowhere was this more evident than in the mid-80's GM cast iron engines where the freeze plugs would rust out and start leaking. PITA to fix that "little problem". The parts would cost a couple of bucks, the labor hundreds!
  • marblazemarblaze Member Posts: 16
    how do i programm the remote for my 99 S-10 BLAZER
  • tidestertidester Member Posts: 10,059
    The Chevy Blazer GMC Jimmy Maintenance and Repair topic might be a better fit to your question. :)

    tidester, host
    SUVs and Smart Shopper
  • markindenvermarkindenver Member Posts: 1
    Concerning your problem i am having the exact same. Plus one of my oil lines coming out of the radiator is leaking like a stuck pig. Where did you order the hose from and how much was it?
  • jlflemmonsjlflemmons Member Posts: 2,242
    The oil lines can be purchased at NAPA, O'Reilly's, and most other national parts store chains. NAPA cost is around $50.
  • stealthnystealthny Member Posts: 25
    Hi Guys and Gals
    I have a 1997 Blazer 2DR 4X4. I bought it about 1 mo ago and have had nothing but problems. My biggest problem is I cant seem to get it inspected. I have over 200 miles on it since I replaced the battery but when the Mech Hooks up the "DREADED" computer all we get is a reading that says Not Ready To Read. any suggestions? If I cant get it inspected I cant use it. I do have some small electric problems IE:
    My compass is backwards, my fuel gauge doesnt work, and I dont believe my temp gauge is working.


  • punkeypunkey Member Posts: 1
    edited February 2010
    I am new to this forum so hello to all. I have been reading several problems with surging around 1000 to 1500 rpm. My blazer is a copy-cat. Seems that when it desides it wants to, it will jump back and forth. It doesn't matter what gear I have it in. I have tried it in 3rd and it continues just as it did in overdrive. What have you all found to have helped your problem. Thanks!

  • texassun13texassun13 Member Posts: 1
    My 93 blazer is doing the same thing. I was tiold to change the distributer cap and rotor. Didn't solve the problem. The shift light blinks on and off when shifting andf when driving, and it feels like the motor wants to stall. Somedays I have no problem and the truck runs fine. I'm lost to as what is going on, could someone please help me out. thank you,,John
  • fireman14fireman14 Member Posts: 1
    edited March 2010
    On take off and normal driving my blazer seems to stall or sputter then runs fine again. I have replaced the distributor cap, rotor button, plug wires, plugs, egr valve, fuel filter, and the mass air flow sensor. The only thing that has helped was the mass air flow but after driving a few days it starts acting up again. I have already replaced it again with same problem. Any help would be greatly appreciated. Thanks
  • coolincoolin Member Posts: 1
    edited April 2010
    My 98 Blazer does the same thing as yours. It's been running like this for 8 months. This moring, on my way to work, it sputter so hard I thought it was going to stall.

    It's to the point were I won't dart in front of traffic unless I have plenty of room. This way I won't interrupt the flow of traffic and get rear ending. I never know when it will sputter.

    I took it to a good repair shop and they cleaned off a sensor and it helped for a week, then it went back to the stalling/sputtering. I hope whatever the problem is it will be a cheap fix. I just spent $800 fixing something elese. I did not mention the stalling, I was still in shock from the $800 problem.
  • rfletcherrfletcher Member Posts: 25
    1991 S10 Blazer 4X4 4.3 L 187000 mi. Truck in excellent condition, used every day and normally runs very well. Intermittently, the engine dies, at any speed, without warning.. Will restart but may or may not stall again within a few minutes. May be heat related. After it sits for several hours, will operate perfectly for weeks or months. Problem started last fall. Replaced ignition control module, Dist. Cap, Rotor, Plugs etc. Replaced both temp. sensors . and oil pressure sensor. Fuel pressure was and still is normal.[ Had a qualified mech. check it again this week.] After all the "Easter Egging" last fall, did not fail again until March then again in April but ran perfectly until last week. Truck was in shop all day, with three mechs. driving and testing.. Can find nothing wrong.. No codes. Normal driving conditions are short trips with frequent stops. Has never failed . Each incident was on an 80 mile round trip. Forty miles over, no problem and sits for two hours. Forty miles back and has stalled up to six times at 65mph and / or in heavy traffic at very low speed. Will restart, usually very easy but occasionally, all but kills the battery. :confuse:

    It's driving me NUTS and not doing my pocket any favors either.

    Thanks for any suggestions
  • duntovduntov Member Posts: 133
    I think I may have covered this one before. Anyway, you should always use a conductive lube or paste on the ICM head sink in the distributor. Do not use dielectric grease or silicone greease such as SIL Glide. Dielectrice lube is a insulator. Always replace the two ICM moumnting screws also. They ground the ICM and can corrode due to moisture and electrolysis. Unfortunately, the monting screws are a dealer item, part no. 10469668. The heat sink paste is Arctic Silver 5. and can be purchased as any computer electronics store.

    The ICM is sensitive to heat and ground and will intermittenly fail when the heat is excessive there high resistance to ground. .
  • jlflemmonsjlflemmons Member Posts: 2,242
    Try applying a heat gun to the crankshaft position sensor. These will only set a code if the failure occurs three times without cycling the ignition. If weak, they tend to fail when hot, and at higher rpm. The unit is what's called a Hall Effect sensor. Reads the magnetic pulse from the crankshaft and will kill the engine if it doesn't "see" the pulse.
  • rfletcherrfletcher Member Posts: 25
    Thanks, I will certainly do as you suggest. I think a paste came with the new ICM but have no idea what it was. I had a gut feeling that it was heat related but not in this way.
  • rfletcherrfletcher Member Posts: 25
    Thanks for the help. I will check that too. Has never set a code but then the OBD1 dosn't read a lot. Seems the guys in the shop here lack your experience.
  • rfletcherrfletcher Member Posts: 25
    As you suggested, I pulled the ICM, cleaned all surfaces, and reinstalled it with the only silver product I could find. Holiday weekend. Today, in the very fine print I noticed this product, while claimed to be 99.9% pure silver and made for high power heat sinks, is not electrically conductive. Makes no sense but now I feel that I should pull it again. Your opinion.
  • duntovduntov Member Posts: 133
    Arctic Silver 5 is THERMALLY CONDUCTIVE, and was designed to conduct heat, not electricity. The heat sink for the ICM is designed to conduct heat away from the module and Arctic Silver 5 enhances that conductivity.

    New fasteners provide a good electrical ground for the ICM and should be replaced when the ICM is replaced.
  • rfletcherrfletcher Member Posts: 25
    I understand the thermal issue but misinterpreted your post as to electrical aspect of the paste because of the potential failure of the screws.. Turns out the paste from Radio Shack is in fact Arctic Silver 5 marketed under their label so I am good to go. Will see what happens. Thanks
  • zassoffzassoff Member Posts: 2
    i have a 95 chevy blazer that is running like i'm trying to burn pond water. i can pour sea foam in the tank and for a few days it clears up, and then back to the problem again. it also is, apparently, having vaccum problems. when it is running poorly, if i put it under a load ,such as going up a hill, the a/c will start to blow through the defrost ports. the brakes also feels like i'm stepping on a brick. it furthermore will start to overheat during this time-any suggestions?
  • rfletcherrfletcher Member Posts: 25
    Since post of 6 July have had no more stalling in traffic. Thanks duntov. Now,again intermittently, the engine will not start without WOT, but it will start, every time. Hot, cold, never know when it will occur. Following may or may not have to do with problem When it starts, vac is steady at 20 in. hot idle. WOT, momentary drop then rapid increase to 23 in. MAP test; KOEO, ref. voltage steady 5. Output term B 4.91. Hot idle output 1.45 / 1.503. Then the questionable appears. WOT [ vac as above] output drops to .923 then rises back to near idle values. Chilton book calls for rise to near 4.5. Have no idea how to interpret this. Also suspected EGR so did following; Can not see movement on this one so temp. connected vac pump in place of TBI. A small vac, 2 or3 in., caused engine to stumble, more vac, engine died. Found EGR solenoid inoperative. Very high resistance in coil. Applied 12 volts directly but no action. Again, have no clue what or if this means anything to starting problem. Of course these test would not account for a valve that is intermittently stuck slightly open. Prior to this the idle had become rough. Quite a lot of vibration, especially with AC on. This is also intermittent. Shop told me it was motor mounts. These are the same guys who could find no problem concerning the previous post.
  • wallawallaacrewallawallaacre Member Posts: 2
    Hi, does anyone know how to or can provide a diagram on how to replace the ignition module in the steering column. I looked when would not start and thought I fixed but when the column is tilted up it does not want to engage. Turn key and nothing. Lower column and it turns over. Any help would be greatly appreciated. Thanks
  • femekafemeka Member Posts: 2
    i have been useing my blazer for some years now ,but last two months i drive to a supermarket and parked after shoping wen i came back try to start the car but car denied to start after many hours i took it to workshop for two months electricains and mechanic could not not start my chev they have tryed to change the brian box, coil, sensors, but the problem still remian thesame, pls if there is any advice or help you can give i wil realy apreciate. please i need ur reply on this matter.
  • femekafemeka Member Posts: 2
    please i need ur help guys, my chev blazer 2000 model has serious problem it dosent start it only crank i have change brian box , coils , sensor, but the problem still remain thesame , there is normal flow of current from the brainbox to the coil but from the rutor to the coil there know current , i have change the plug wires, rutor cap , the problem remain thesame, please i need your help.
  • getterdone1getterdone1 Member Posts: 2
    I have been having issues with my 1994 Chevy Blazer 5.7. I have had it tested by a shop and the codes that came up said my MAP sensor was having issues and it was running lean. I replaced the MAP sensor, EGR valve solenoid and it was no better. I was on the freeway the other day and my gas pedal sucked to the floor and the truck was accelerating. I turned the key off and back on but the engine was revving so high the truck never completely shut off but it did release the gas pedal. Why would this happen?
  • getterdone1getterdone1 Member Posts: 2
    I have a 1994 and it is also doing this. I have replaced several things and the item that gave me the MOST improvment was replacing the PCV valve now It seems to do it much more in colder and not so much when it's warm. Still lost as to what the rest of the problem is
  • rx7420rx7420 Member Posts: 3
    sometimes it wont start when it does start it idles fine for a bit then when u put it in drive it will be ok then the rpms will surge to 1300 and at idle around 1800 and stay that way till i shut it off i thought maybe the idle control motor was bad so i replaced it and it didnt fix it any ideas
  • rx7420rx7420 Member Posts: 3
    hey my 95 blazer is kinda havein the same problem did u ever figure it out?
  • rfletcherrfletcher Member Posts: 25
    edited September 2012
    Blazer Sport 4X4 4.3l TBI 185000 miles. No trouble codes. Code 12 only. Has a long history of stalling at high speed, rough idle and poor gas mileage. Gave up on DIY. After four professional shops and more money than I care to think about, finally found the problem, or so I thought. Last shop found, inside, the throttle body totally encrusted with carbon. One vacuum port had to be drilled out. Cleaned body and installed overhaul kit including the fuel regulator and injectors. Replaced O2 sensor for the third time. Truck ran as new for a few weeks. Fuel consumption same as when new. Was never that great. Now: does not stall at high speed but does stall on rapid deceleration. Intermittent rough idle and poor gas mileage. In desperation, purchased an ALDL to USB interface for the laptop. Running WinALDL. Data scan indicates INT set to 128 as is normal for open loop. BLM counts from 0 to 256 then starts over. Do not know what this count means. O2 does not hunt. Never changes more than .465 to .570 during warm up. Temp. was a little low so changed sensor. Now 287F. No effect. All other sensors are normal. It appears to be stuck in open loop and running very rich. I am in over my head and treading water. Does any of this mean anything to anyone? Defective ECM? Defective wiring? Thanks to anyone and everyone.
  • usnavymiochaelusnavymiochael Member Posts: 1
    When I start it some times the brake light stays on,fuel guage does'nt work, air bags warning lights on. I was thinking maybe ignition switch. I have a 2001 I just bought with a bunch of electrical problems. Is this pron to these models? I appreciate any help I can get. Thank you all.
  • jnskuehljnskuehl Member Posts: 1
    I have a 2008 Trail Blazer that we purchased in April of 2009 with 8,000 miles on it. In 2010, at 51,000 the engine blew. GM refused to pay for it because they said it was "lack of maintenance", which is impossible as we have a Dodge with 320,000, a Honda with 275,000 and a Chrysler with 150,000 on them. They finally paid to have a new motor put in. In 2011, the exhaust manifold cracked just as a recall came out. GM replaced it with no problems. In 2012, at 121,000 miles, the exhaust manifold cracked again. GM refused to pay for it but I argued and argued because there was only 30,000 miles between them. They finally agreed to replace it if I signed a waiver stating they were not responsible for any further problems. Of course, I refused to do that. The recall was warranted to 120,000 miles anyway. We are now at 140,000 miles (89,000 on this motor) and it has a "bad head" in cylinder 3. The estimated repair is $4,000.00. GM again refuses to do anything. I'm initiating the attorney general and we are seriously considering a class action suit against GM, as this is such a common problem according to what research I've done. Please give me input on your issues if they are anything like ours. The more names I have for the class action suit, the better! Thank you!!
  • friedduckyfriedducky Member Posts: 1

    hello, i have a 96 chevy blazer 4.3 ive tried everything to get it to start it tries to start at 3/4 throttle but then quits can anyone give me an idea what the problem might be, it was running the just shut down on the hwy and havent been able to start it since then thank you

Sign In or Register to comment.