Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Chevy Blazer GMC Jimmy Maintenance and Repair



  • mmmkayemmmkaye Posts: 2
    After 5 mechanics, I finally figured it out. For some reason my vehicle wasn't showing any trouble codes and no indicators would come on. Lazy [non-permissible content removed] Mechanics wouldn't touch a thing unless an error message came up on their diagnostic. What ever happened to look, feel, and listen? Catalytic converter was plugged really bad. I suggested a while back that could be the problem, but the mechanic didn't want to screw around with emmissions standards, etc. Finally found someone willing to replace it (which involves cutting out the old and welding in the new). Jimmy runs like a rocket now. My shifting problems, torque issues, everything is back to normal (and MUCH better gas mileage now too) Cautionary note... if anyone suggests you cut the cat converter out completely be wary. I've been told it will cause back-pressure problems and screw up your injectors in the long run. Hope this helps...
  • jlflemmonsjlflemmons Posts: 2,240
    Along a similar note, I was told by a couple of different "authorities" that my cat was the source of noise in the exhaust. I got under the Blazer and found a large dent in the muffler. Got a neighbor to hold the throttle just above idle where the noise was occuring. Lo and behold, the rattling noise isn't in the cat, it is quite obviously coming from the baffle knocked loose in the muffler!

    Sometimes we need to look and listen with our own senses, instead of trusting what a book or computer tells us.

  • auto9999auto9999 Posts: 86
    My dealer says that my 2000 Blazer, 4WD Trailblazer-trim 65,000 original miles, needs repairs on rear pinion leak and loose idler arm, both to be replaced. They say that they can be replaced at the next engine oil change. Their quote is about $300 (including wheel alignment) and $160, respectively. My question is how urgent these repairs are? I do not hear any grinding noise or anything, and the truck is running very smoothly.
  • repairdogrepairdog Posts: 948
    Are the tires wearing up front and does it pull or wander - then should, be done. Idle is on the pass side and a $25 part and align is $75 so thats some labor on replacement. I would think the lower ball joints also are really loose by now more than the idler arm! Known Blazer weak point.
    The rear pinion leak - where the front seal where the driveshaft comes out - look under at amount leaking - if really minor then no hurry (see the 1/2" plug halfway up the rear thats the fill plug so use a 1/2' drive extension, just the square end, and open and 80-90 gear oil should be to that level - stick finger in to feel. If leaking thru the rear cover again depends on amount and if thru an axle out the brakes that need to be done now so brakes work correctly.
    By 65k you should have also had the trans filter/fluid done and the transfer case fluid (if AutoTrac 4 button then transfer uses blue syn fluid not red Dexron as the transmission does). Hope you have had the Dex cool changed too or you will soon be facing some major cooling system sludging - no matter what the dealer says the GM 5/100 Dex cool has so many suits its not funny but changing and staying on top (watching) the reservior level is key.
  • auto9999auto9999 Posts: 86
    Thank you , Repairdog, for your quick reply. I will investigate these items.
  • jlflemmonsjlflemmons Posts: 2,240
    Is the lower ball wear primarily a 4WD issue? The used 2WD Blazer ('99) I picked up appears to have the original ball joints at 78K and the wear indicator looks good and the steering is tight after replacing the center link.
  • repairdogrepairdog Posts: 948
    Yes 4wd issue. The 2wd ones are larger design. The 4wd have to clear the CV axle so are smaller and thus weaker. My daughters 2wd has 170k and original ball joints while my 4wds all had them by 80k.
  • Hi I read all the messages and just laugh inside with sheer fustration of seeing alot of the same prob.s. Well right now I am looking to find some info on throttle cables or Accelerator Cables which ever you would like to call them as long as i get some were with this i dont care to much as to what you call them. I have a 96 gmc jimmy and need one! as well as many other parts even ones i have replaced not to long ago. but for now where to look and what size to know when finding this part if any one has any insight? I plan to call a few places tomorrow when people get back to work for it is late in maine and we all need our long needed sleep.haha. Of corse it seems to happen when its to late. :cry:
  • jlflemmonsjlflemmons Posts: 2,240
    Thanks. That clears up my confusion. Here in Texas we see a lot of 2WD and I haven't heard any complaints about premature ball joint wear. Now doesn't it make sense that the vehicle you build for offroad would have smaller joints???

  • First time posting to this list which has been a great help in the past. I'm the second owner of the truck, I've had it now for about three years. It's high millage with 160,000 miles but at the time I purchased it with 150,000 miles I considered it a good buy because before it was owned by a group of sail plane pilots who kept every record on the truck and it was very, very well maintained. In early Dec. of last year my Jimmy which has the 4.3L Z engine died on me but after a change of plugs, wires, cap and rotor, fuel filter and the addition of a Jacobs Electronics Ultra Coil the truck up until last week ran better then ever. It now dies at idle and when I go to accelerate it is very low on power although it seems to be firing on all six cylinders. when it shifts it's at high revs and the truck lurches and top speed seems to be about 35 mph. I've once again changed every thing I did back in Dec. and on the advice of an engineer at work I changed out the oxygen sensor with no improvement. I'm at wits end am sadly without a code reader. Any ideas would be greatly appreciated!!
  • repairdogrepairdog Posts: 948
    Advance and Autozone and most stores will read the codes for free (this assumes the SES light is on so a posted code). They also have a free handout that tells you how to read them out yourself cause thus is a 90 so believe old system and you can get the light to flash the code out. Very common is the old CPI and nut kit which is the injection under that upper intake - it leaks and does what you stated so do a search on CPI and Blazer and you will find many answers.
  • Thanks for the speedy reply repairdog. I see that you have been a great help to many. I've been pouring over my Chilton manual this morning trying to find any info on the CPI unit but with no success. I've done the search as suggested and have come to guess (probably mistaken) that CPI stands for Central Port Injection. My jimmy being a 1990 model is equipped with the Rochester TBI unit. :confuse: Would this still have the CPI and nut kit (supply lines)? Again, many thanks!!
  • repairdogrepairdog Posts: 948
    Sorry, missed that 90 date. No CPI on the TBI models only the electric injectors on the throttle body. You have the book so now check the fuel pressure to see if fuel pump related or relays.
  • No problem repairdog, figured that out this morning. have done a host of things mainly checking and re checking things in leu of having much to go on as far as diagnostic tools. I've noticed that there is no fuel entering the top left throat of the TBI. Is this the secondary? Noticed a pinched wire leading to the injector. Wire integrity seems ok, have insulated it the best I can. Have wired in a Jacobs FC 1000 ignition module and it starts with no problems so I can rule out any problems with the ignition system. I work at Mallory Electric so I guess I can talk to a few people there and maybe find out more.
  • I’ve been having a front diff. actuator problem with my 4wd ’02 blazer ZR2. With the vac. line above the driver side fender plugged in the actuator won’t engage below 35mph. While on the highway above 35mph (roughly) the actuator engages. It will not engage with the vac line unplugged at that speed. Are there any long term effects leaving the vac line unplugged while only in 2wd and does the speed have any effect on the vac switch itself? Is the vac switch the source of my problems? Thank you for any help
  • repairdogrepairdog Posts: 948
    Can't say for sure but if you disconnect the vac line under hood to the 3 port you must plug the engine side off (golf T is great). The 3 port switch on the case is about $20 so try that first (based on 3 button 233 case - tag on case - not the 236 4 button Autotrac case). Check all lines under and up to the front actuator that the vac engages and that pulls a cable to lock or coupler the pass side axle. Then at the same time (when you select 4Hi) the encoder motor on the case steps and engages the front driveshaft. So, once you select 4Hi axle couples and front shaft engaged and light on dash stops blinking and goes solid on 4Hi - if not the TCCM (4wd computer) did not get readings from the sensors on the axle and case confirming status.
  • repairdogrepairdog Posts: 948
    All mine are newer models so this is a reach back. The fuel pressure per Haynes is 9-13psi. Assembly has the throttle body and fuel metering controlled by the throttle position sensor(TPS) on the throttle butterfly shaft which signals the PCM that then determines the mixture. 1 injector is primary and 1 secondary as I recall (had a 350 Suburban TBI). Also an idle air control (IAC) on the TBI that maintains idle by air mixture. $15 Hayes shows most of this.
  • frschevyfrschevy Posts: 2
    I have a 04 chevy blazer 6 cyl 4 wheel drive.
    I purchased in Jan 07. (39,000 miles)
    Its been back to the dealer 4 times for stalling.
    I'm just driving down the road and its shuts off.
    I still have power but the engine quits.
    so for all that has been done is (replaced)
    the distributer cap and roater,the coil and something attached to it. They can't figure it out. I don't get any
    check engine lites. Im pritty sure the problem is electrical,but who knows. Can anyone help this is driving me crazy.
  • jlflemmonsjlflemmons Posts: 2,240
    Crank shaft position sensor??? If intermittent it will not set a code. But the fail mode is that it thinks the engine is not turning and will shut off the fuel and ignition. One way I have isolated it is to try this. When the engine quits, WITHOUT TURNING THE KEY OFF try and start the engine. If it will not fire, turn the key to OFF, count to ten seconds or so, then see if it will start. If it fires right up, you may have an intermittent sensor. I have seen this on late 80's and early 90's, but the discription you give does seem similar.
Sign In or Register to comment.