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1989 Buick Electra 3.8L balancer
I need to remove the balancer to access the sensor,unfortunately I have never seen this type of balancer before.The front is smooth with no access to the threads which would normally be used with a regular puller.It looks like my only option is a jaw style pul...		 View
2000 Buick Park Avenue 3.8L Drivers Vents
Any GM Techs seen this before? Passenger side cold, but driver side cool when set to 60. Change the temp to hot and both sides are good. Just can't seem to get driver side to get as cold as pass. Removed driver air mix door and moved manually, still not as col...		 View
2003 Buick Rendezvous 3.4L Accessories
This jewel blows fuse #36 constantly. Its a power source to the bcm. We found coffee spilled all inside the console & in the connectors etc. of the bcm. We replaced the bcm, cleaned the connectors & still pops the fuse. We went through each wire into both bcm ...		 View
1998 Cadillac Eldorado 4.6L blower motor
This vehicle has automatic ac control. The blower motor will intermittently stop working for 10 to 30 seconds and then starts working. I set the controls to both automatic and also non automatic and the problem continues. The panel remains lite and the compres...		 View
1998 Cadillac DeVille 4.6L Poor Idle Quality, Misfire, MIL Lamp on
customer just got this car came in with check engine light on PO300 RANDOM MISFIRE counts on cylinders 1,3,5,7,only at idle smoke test/replaced intake gaskets, unplugged o2 much better result, 2 new o2 sensors misfires return, fuel trims on bank 1 goes neg 15,... Trouble codes: p0300 (random misfire).		 View
2004 Cadillac DeVille 4.6L Hard start
This is a very stupid question. I am not familiar with the Cadillac interior. I want to check the battery (possibly replace). I found it located under the rear seat cushion. However, I have no idea how to remove the cushion. Please let me know the big secret. ...		 View
1994 Chevrolet Pickup 6.5L No power
I will start by saying thanks to anyone who takes the time to enlighten me about the workings of this 6.5 TD, This is my truck(bought recently/not running), I have a Master ASE cert. for cars and light trucks, but have very little expertise on these Diesels, A... Trouble codes: 36 (Ignition pulse width errorresponse time long).		 View
1998 Chevrolet S10 Pickup 2.2L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall
i have this headache truck from ...well you know where. problem is that the truck will start fine, idle smooth, accellerate fine. all pcm inputs look great UNTIL it goes in to closed loop operation !!! now according to the above data it appears that this truck...		 View
1998 Chevrolet Cavalier 2.2L Stall
Hello iatm members, this one is giving me a hard time to figure out. Cust complaints the car stalls interm coming off the highway coasting, no codes in the system. Looking at the perameters while car stalls and they look to be all in range. The o2 reads lean c...		 View
1998 Chevrolet Camaro 5.7L drive cycle
I can not get three monitors to set during the drive cycle. The car came in for state inspection. We put it on the lift to do the machanicle part of the inspection. When we went to restart the vehicle to move it to the inpection machine it would not start. We ...		 View
2000 Chevrolet Pickup 5.7L Poor Idle Quality
Please help? My head hurts! This truck starts and runs fine most of the time.But after driving for awhile some times it starts to idle any where between 1000-2500rpm,you can feel this on decel.Put in park and rpm slowley declines down to 600-900rpm after an in... Trouble codes: po123b (tps performance).		 View
2001 Chevrolet Suburban 5.3L MIL Lamp on
have a 2001 suburban here that 02 sensor will read low when 02 sensor warms up, reads okay when cold, replaced cat with one from carquest and same problem, replace again with one from napa and same problem, run b1 s2 harness to b2 s2 sensor and reads fine. 02 ... Trouble codes: PO137 (02 signal low bank 1 sensor 2).		 View
2001 Chevrolet Silverado 8.1L 2-3 upshift
I have an unusual Allison problem. This only occurs when the customer has his big 5th wheel camper hooked up. When accelerating in either regular drive or tow haul mode it shifts good until it goes to make the 2-3 upshift. At that time it pauses, clunks real b...		 View
2004 Chevrolet Astro 4.3L No Start
This vehicle stalled while driving and will not restart. My genesys or modis will comunicate with all modules on vehicle. Pid in PCM indicates fuel disabled by VTD (Theft deterent system). Only codes found are u1000, and u1016 codes found in air bag module and... Trouble codes: u1000 (class 2 com. fault in air bag module and t. case module.), u1016 (cannot comunicate with PCM code also in air bag and t. case module).		 View
2005 Chevrolet Express 4.8L No Start
Thanks for your help, regular fleet customer ran this van out of gas. They put around a gallon in it and ran down battery trying to start it. Never did start and had it towed to me. I checked for fuel pump operation and found it running. There is no external f...		 View
1994 GMC Pickup 5.7L No Start, Cuts out
Customer brought in for hard start. I tried starting while he was still here and sure enough a hard start. Acted like timing was way advanced, after it started it seemed to run ok. Customer said he had it to another shop and they said the timing was 11 dec. of...		 View
2000 GMC Sierra 4.3L Misfire
This truck came to our shop not running. We found good fuel pressure but no volume which lead to the filter. Once volume was corrected the truck would run but not idle and a severe misfife was present. The misfire was intermitantly on 4 cylinders but mostly on... Trouble codes: po300 (ramdom cylinder misfire).		 View
2002 GMC Yukon 6.0L ride control
hey everyone, i have a "service ride control" message on my dash. no codes in ecm, bcm, abs, ipc, tcm. there is no esc option on my modis. checked fuses, wiring etc. how do i get diagnostic codes out of this thing. i do mostly diesel anymore so i am a little b...		 View
1997 Pontiac Bonneville 3.8L power windows interior lamps
when this car won't start the power windows don't work when you push and hold the power window down button the lower dash lights dim slowly until they go out after you release the button the chimes sound off. believe it to be a ground problem but can not seam ...		 View
2000 Pontiac Montana 3.4L fuel pump
thanks in advance heres a bald spot creator. we have this montana van that came in with no start in morning.we charged battery checked charging everything ok, advised customer to make sure everything was off .next day dead battery again towed in hooked up batt...		 View
2002 Pontiac Grand Am 3.4L No Start
after 20 or 30 key cycles the bcm forgets password and relearn prossess is required Trouble codes: b2600 (no discript.), b2602 (no discript.), b2960 (no discript.), u1128 (irc), u1088 (s.r.sdm).		 View
2004 Pontiac Grand Prix 3.8L engine
Hi guys got this car in with complaint of an engine noise. When the engine is cold there is no noise, but as it warms up there is a ticking noise[sounds like rist pin]. I tried to cancel out the injectors one at a time to see if noise would change it did not. ...		 View

Fixes & Summaries for GM
Fix/Summary Answers
1991 Buick Century 3.3L No Start
Thank You all Iatn Members. The fix for Buick was having son use paper clip to jump aldl terminals and read codes. A 22 code (related to fuel injectors) was in memory. Following some suggestions, had son disconnect injectors one at a time. Bingo! Car started. ...		 16
1994 Buick Park Avenue 3.8L idiot lights come on, no start
ITS FIXED, AS MOST SUGGESTED I REPLACED COMPUTER AND PROBLEM GONE BUT!I WANT TO SHARE THE OTHER TEST RESULTS I HAD TO HOPEFULLY SAVE THE NEXT TECH SOME TIME. WHEN THE CAR "NO STARTED" THERE WAS 5 VOLT REF AT ALL SENSORS AND AT THE PCM, NO VOLTAGE DROPS AT THE ...		 12
1995 Buick LeSabre 3.8L volt lite on
applied 12 volts to "L" terminal and lite goes out. bypassed pcm and charges properly. replaced pcm and all is well. thanks for the replies.		 4
1974 Chevrolet Corvette 5.7L brake
I guess us old timers need to be kicked in the butt every once in awhile. Turns out the LF caliper was leaking ever so slightly onto the pads causing a pull because of the fluid soaked pads. After finding that, I went ahead and ordered a remanufactured set of...		 20
2002 Chevrolet Malibu 3.1L Engine Noise
Thanks for the help everyone. It turned out that the cat. was slightly plugged causing the exhaust manifold gasket on the front head to whistle slightly due to a loose stud. We installed a new converter and exhaust manifold gasket and Viola! No more noise! Tha...		 11
2003 Chevrolet Express 6.0L power steering pump
I replaced pump again and also replaced both pressure hoses, pump to hydroboost and hydroboost to steering gear. A restriction in a hose was causing pump to fail. 		3
2003 Chevrolet Astro 4.3L No Start
timing chain jumped 180 off, p1626 theft system was from extended cranking time thanks to all that replied Trouble codes: p1626 (theft fuel circuit).		 26
2003 Chevrolet Tahoe 5.3L Stall, MIL Lamp on, Throttle dont open
HI Y'ALL!!! Thanks for all the help. The customer NEVER did return. The three most discussed problem were the yellow power wire possibly being broken at connector or in harness. The MAP sensor, I wasn't looking at that signal while I had it in the shop. Or th... Trouble codes: p1514 (mass air sens tps dont match).		 21
2004 Chevrolet Silverado 6.6L Hesitation, Cuts out, Misfire
Checked everything on Tech 2, from fuel pressure, to MAF, to boost readings. Customer declined further diagnosis. We even called Identifix, no fix. Customer traded in vehicle. Thanks for the replies.		 12
2004 Chevrolet Cavalier 2.2L No Start
to all that helped with this nightmare.I replaced ignition switch tested wires but of course it tested ok.going with my gut and your advise.Thanks for the advice iam sure this will cure my problem,but only time will tell.		 4
2005 Chevrolet Colorado 3.5L cv boots
I installed a new axle on the passenger side and a boot on the drivers side when done I measured ride height it was ok, brakes and wheel bearings all ok. I told the customer he had to get the tires replaced because it was bad on the whole system to run 2 diffe...		 7
2002 GMC Envoy 4.2L engine
Thanks for the info,after talking it over with the tech ,he mentioned how much trouble he had installing the mount.We removed it,ground off the alignment tit,took 90% of the vibration,somehow the mount was twisted, in a bind.Doesnt look like it was in a wreck,...		 2
2003 GMC Sierra 6.6L Excessive Emissions, blue/ white smoke
well thanks to all that replied we put 8 injectors in the unit did not fix it this truck does not use .5 litre of oil between oil changes it stinks of raw fuel out the tail pipe i am out the price of injectors my custom...		 8
1995 Oldsmobile Aurora 4.0L MIL Lamp on
sorry it took so long to post this fix.i took the car to another shop that had a tech 2.they relearned the idle for me and it fixed the problem.thanks to everyone who responded. ken Trouble codes: 85 (idlelearn at maximum authority).		 10
2003 Saturn L200 2.2L fuel&temp gauges
Bcm was bad //Thanks for the help guys.The saturn techs see this all the time. 		3
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