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Open Help Requests for GM
Help Request Answers
2001 Buick Park Avenue 3.8L Unknown
hi all i have this Buick that is kicking my you know what. came in complaint of a bad vibration in front. test drove on highway and verified concern. real bad vibration at about 60 mph. felt like a bent axle or bad u-joint. seemed to be worse on acceleration, ...		 View
1997 Cadillac DeVille 4.6L compressor
I don't do a lot of AC, but this one looks like a compressor. System has a high low side and a low high side. Compressor clutch is engaging fine. Customer had the car to Jiffy-Lube and I think they overcharged the system. I was thinking about evacuating the sy...		 View
2002 Cadillac Seville 4.6L abs tcs
To all valued techs Caddy has abs tcs red brake light all on .codes in ABS c1277 (torque request sig malfunction )c1298 loss of comunication ,same codes in magnasteer .elec suspension has code c0710 steerin pos sensor .I also checked pcm and it has U1040 abs ...		 View
1990 Chevrolet Lumina 3.1L Excessive Emissions, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, Poor Fuel Economy
This one came in running rough, dies, bucking, surging, backfiring. Checked for codes and none present. checked data and MAP/Baro at 3". TPS at 0v. Tested 5v ref circuit 0v from ECM. Tested power supply and grounds all good. replaced ECM and same problem occur...		 View
1997 Chevrolet Pickup 5.7L No Start
TRUCK WAS TOWED IN CRANK NO START. Has spark,60 psi fuel presure and no injector pulse. Have check cam and ckp signal at pcm both are good. Have power through inj to pcm koeo,when cranking the pcm pulses the inj once and then will not ground them. Can spray th...		 View
1999 Chevrolet Pickup 5.7L fuel
truck came in no start,hooked modis up found p1626 & u1192 did the vtd relearn truck started fine,clear codes,p1626 came right back.after trying to start again no start did relearn worked fine.i dont know much about this code,is it something dealer has to fix ...		 View
1999 Chevrolet Suburban 5.7L compressor
Hey guys hope you can help,replaced the compressor, drier, orifice tube because of leaking compressor. The discharge line does not get cold at all.The suction gets hot at the compressor and through the condensor until it gets to the orifice tube.Hi line is ice...		 View
2001 Chevrolet Silverado 6.6L Mechanical
We have a truck with the allison trans for a trans service.We replaced both filters but did not do the flush because our machine will not handle the pressure.Everything went smooth till the test drive after.Its as though we lost we lost fluid pressure.We lost ...		 View
2004 Chevrolet Silverado 5.3L radio
this is my personal vehicle and i am trying to upgrade from a standard cd player with steering wheel controls to a 6 disc factory cd player. initial radio works great, my hunch is that the gm remain is no good. before attemping this upgrade i checked all wirin...		 View
2006 Chevrolet HHR 2.2L shift interlock
I am posting this because i could find no other posts or info for this system. What i had was a gearshifter that would freewheel- would not lock in any gear, BTSI had no affect on it. Also the ignition key would not turn back far enough to get the key out of t...		 View
1993 Geo Tracker 1.6L No Start
The owner of this vehicle tried to fix it for a few months, and never did. Brought it into the shop and I discovered it had no injector pulse, I replaced the pcm and now I have injector pulse. It has 150 psi across the board, and the spark plugs are firing in ...		 View
1995 GMC Pickup 5.0L Poor Idle Quality, Cuts out, Stall
Here is a truck that has me pulling my hair out. 1995 GMC 1500 5.0 auto trans. Vehicle will not Idle and when you accelerate in park and under load it lacks power and seems like it is not getting any fuel. If I slowly step on the throttle it seems ok but when ...		 View
1998 GMC Jimmy 4.3L Poor Idle Quality, Hesitation, knocking at cruise
iam new owner for jimmy 1998 , i get the car at winter and its hesitated too much after i clean the injectors and replace the balancer and plug, wires, air filter, fuel filter and the vechile become more best but still hesitated and i dont know what i make , s...		 View
2003 GMC Sierra 6.6L controll???
No snow!! the snow flake light on climate controll has line thru it. Have not seen this before, A/C non op, when push A/C button snow flake light comes on but has line thru it. scan tool shows no A/C command, However if I turn defrost on and temp to 60 A/C blo...		 View
2001 Oldsmobile Aurora 3.5L Misfire, MIL Lamp on
So this is the worst kind of problem you can have...one on your own car... I'm in the process of buying this Aurora from my mother in law, after telling my wife for the last year that we didn't want to touch it cause these things are problem pits! It set the m... Trouble codes: PO131 (O2 - 1 low), PO137 (O2 - 2 low), PO300 (Randommultiple misfire).		 View
1997 Pontiac Grand Am 3.1L engine oiling/ valve train
Have oil pressure light on and very rough rough run. Mechanical knock/tick that seems to be coming from valve train . Engine was left running for somewhat extended period of time and knock/tick did not get worse, nor did engine exhibit a seize condition which ...		 View
1999 Pontiac Firebird 3.8L negative fuel trim
Howdy, This fireturd came from a neighbor shop they dropped a boneyard motor in it and then dropped it at our door. We cleaned the injectors and valve ports replaced a "made in china" coil pack that had a poor pattern, fixed a loose ecm connection and reset fu...		 View
1991 Saturn SL1 1.9L Odometer
Help! Boss says the odometer on his car quit three after he bought the car. Speedometer works great, all other gauges and lights work. Started out by replacing the dash with a junk yard unit twice. Didn't work. Unplugged the passive restraint modual and cruse ...		 View
2001 Saturn SL 1.9L engine
1.9 engine. replaced pcv and front o2. blowby add -10 to stftrims. keys on cam and crank shaft solid. output of cat is running cool at idle. no exhaust back pressure. current checks of injectors are even, matches ecm pulse time and all are shutting off. inject...		 View

Fixes & Summaries for GM
Fix/Summary Answers
2000 Buick Century 3.1L Misfire
Had many (41) good replies to this help request. Most referred to the basics spark, fuel, compression. Many believed it was a problem with the valve job that was done or a possible problem with the lifters. Because the school year ended we had to send the vehi...		 41
2007 Buick LaCrosse 3.6L XM module
Thanks to the 4 responders who helped so much, and on the weekend, too. Richard from FL led me away from the disassembled dash, back to the trunk where I had overlooked the XM module, aka Digital Radio Receiver DRR. He responded in less than an hour. Big thank...		 4
1986 Chevrolet Corvette 5.7L battery
Thank you to all who replied. I found circuit breaker for power seats and locks- tied in with theft module. I assumed the pattern of the pulse would lead me to module. Wrong! The problem lies in passenger seat. I disconnected connector under seat and draw is g...		 17
2000 Chevrolet Silverado 5.3L MIL Lamp on
I RECEIVED A FEW GOOD RESPONSES POINTING TO THE THE CARBON CANISTER ALSO GETTING PLUGGED. I PULLED IT OUT AND IT WAS FULL OF GAS. APPARENTLY THE OWNER DOESN'T KNOW WHAT TO DO WHEN THE GAS PUMP CLICKS!!! NEW CANISTER AND A BAY TEST WITH THE MASTERTECH AND ALL I... Trouble codes: po446 (evap vent).		 3
2001 Chevrolet Lumina 3.1L MIL Lamp on
Well I am going to count this one fixed. I checked for any blockage in the vent line and found nothing so I started looking at the fuel tank pressure reading and it was showing a higher than normal reading. Modis trouble shooter specks said normal voltage re... Trouble codes: p0446 (evap vent control problem).		 3
2003 Chevrolet Malibu 3.1L No Start
Thankful for the requests, but the customer has not brought the vehicle back in yet. I have performed most of what people have requested. My view is the problem is most likely in the ignition switch		 10
2006 Chevrolet Malibu 3.5L steering
thanks for all that replied. we reprogram the steering module and the customer has not come back since. she seems to be happy. thanks to all that responded		 4
1993 Geo Tracker 1.6L No Start
Thanks for the help, I had the pcm rebuilt and I now have injector noid. Unfortunatly the owner of the vehicle played with it for 3 months so I am still trying to find what they have messed up.		 9
1995 Oldsmobile Aurora 4.0L Poor Idle Quality
The warranty replacement of the ISC motor performed by the dealer fixed the problem...Buyer beware even when getting oem parts. Turned out well in the end, my original diagnosis was correct ISC motor failure. Thanks to all who replied. Trouble codes: 52 (Snap on Modis internal fault in PCM historical), 109 (Snap on Modis Checksuum error cant read romhistorical).		 6
1998 Oldsmobile Bravada 4.3L alternator
I want to thank those that sent replies, I found that the alternator had one diode that showed a problem and installed an ac delco reman. The charging system seems fine now. The same day the customer called and said the car died and would crank but not start...		 7
2001 Oldsmobile Aurora 3.5L Starting
Well guys I have nothing to inform you about because it has been five days now and from the time I posted the help request until now the car has worked perfectly. Thank you for all your help.		 6
1991 Pontiac Grand Am 2.3L Surge, Cuts out
well its fixed but inever found out why the temp. read so high it may have been my stupid modis,which i hate,any way it turns out it was basic.it only had 20psi fuel pressure.installed new pump and every thing was dandy.thanks for all the help.		 9
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