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Open Help Requests for GM
Help Request Answers
1997 Cadillac DeVille 4.6L MIL Lamp on
well first i would again like to thank all for the previous help on this one. i thought all was well on this vehicle after cam timing set properly. we had been fighting a p0340 code. i was performing final test drives to verify repairs when cel light popped on... Trouble codes: P1139 (ho2s insufficient switching bank 1 sensor 2 pre-converter), P1140 (ho2s transition time ratio bank 1 sensor 2 pre-converter), P1571 (traction control system pulse width modulated circuit no frequency), P1632 (theft deterrent system fuel disabled).		 View
1999 Cadillac Seville 4.6L no compressor engagement
customer had at another shop charged a/c system.compressor does not engage.pulled codes i am getting code 1605 loss of hvac serial data.alldata gives no specific tests.connected tech 2 to activate compressor still no luck.checked all fuses /power to relays eve...		 View
1994 Chevrolet Pickup 6.5L MIL Lamp on
Truck runs ok, no stalling, a little hard to start but not bad for the mileage. Have read the updated TSB but it only confirms what I already knew...the problem is intermittent..end of trouble tree...gotta love it. Injection Pulse width is not frozen but hover... Trouble codes: 35 (36 -), 36.		 View
1997 Chevrolet Lumina 3.1L No Start
This is my sons car. I am retired so that I dont have access to all the books etc. I do have a OBD-II Scanner. The problem is on a very hot day the engine will shut off while driving or standing still. The gas gauge will go to full. There will be no ck engine ...		 View
1997 Chevrolet Pickup 4.3L Hesitation, Cuts out, MIL Lamp on
This truck came in about 2 weeks ago with a locked up ac compresser. After putting a system in I road tested truck and just as I was getting back to the shop the truck began to loose power and started bucking and cougfing through the throttle body. I drove a l...		 View
1999 Chevrolet Tahoe 5.7L Cuts out, Stall, MIL Lamp on
when vehicle came in cust states car would hardly run and buck and surge . i drove it and it feels like it is just shutting down with scanner on it i have po335 ckp interm and while driving the only thing i can see is when graphing data is rpm is spiking to 75... Trouble codes: po339 (ckp intermintant).		 View
2000 Chevrolet C6500 7.4L ebcm
No communication with scan tool. Found corroded and broken wires going into the ABS module under the vehicle, Repaired wiring to the ABS module. Codes: C0241, C0242, C0245, C0246, C0251, C0252, C0255, C0256, C0265, C0267, and C0281. Codes C0241 - C0252 are EBC...		 View
2000 Chevrolet Silverado 5.3L Poor Idle Quality, Misfire
This truck runs rough at idle and engine light on, was the concern. check plugs and wires ok. Pressure check fuel system, Had 49 psi. Spec is 55 psi. pinched off return line, no change. if anything dropped 1 psi to 48 psi. Replaced fuel pump. Pressure increas...		 View
2001 Chevrolet Silverado 5.3L Safety
We have this vehicle that keeps coming back into the shop. The problem is that the red brake light and the yellow ABS light will come on intermittently. Turn engine off and the lights go away...sometimes. We have checked the entire braking system and find noth...		 View
2001 Chevrolet Impala 3.4L MIL Lamp on
OK Here we go. Car came in for service and Engine light on. This thing will not comunnicate with the scanner (Snap-On Brick) in either generic or vehicle specific mode. Checked all the fuses and fuseable linkes. Also checked the aldl and the ground and and the...		 View
2003 Chevrolet TrailBlazer 4.2L throttle body
there is a ratcheting type of noise coming from the throttle body when first turning key to run position. I suspect I need to replace the tb assembly, just wondering if anyone has had experienced this.		 View
2004 Chevrolet TrailBlazer 4.2L blower motor
2004 trailblazer rear blower motor works only with driver control switch . passenger blower motor switch will not turn on auxillary blower motor . has anyone seen this before . wires on rear blower switch are not changing in voltage or signal at all . may be f...		 View
1996 GMC Savana 5.7L IGN A fuse
Vehicle was towed in with a no crank situation and dash warning lights or gauges inoperative. Traced problem to blown 40amp IGN A fuse in underhood fuse box. Checked for shorts in circuit from fuse panel to ignition switch to starter. Tried replacing starter -...		 View
2002 GMC Yukon XL 5.3L Misfire, MIL Lamp on
Thanks in advance for all your help! I have this truck that will only misfire for about five seconds on a hot soak condition, 1 out of five times. When the problem occurs all even bank cyls. experience misfires. When this is happening cyl. #6 counts three time... Trouble codes: P0306 (6 cyl misfire), P0300 (random misfire).		 View
1995 Oldsmobile Aurora 4.0L no power
car came in with miss,found bad plug.replace plugs and miss is now gone,but the car has no power and vacuum is low.car runs good but has no power at all.I have block egr valve,and brake booster,no help.sorry I can't give you any data I don't have a scanner for...		 View
1995 Oldsmobile Aurora 4.0L Poor Idle Quality
the Ics motor Ratchets when the key is turned on or off, makes no adjustment to idle speed, the idle speed starts out at 1500, then climbs to excess of 3000 rpm,exhaust superheats to the point of causing a fire in less than 5 mins, so running the vehicle for a... Trouble codes: 52 (Snap on Modis internal fault in PCM historical), 109 (Snap on Modis Checksuum error cant read romhistorical).		 View
2005 Pontiac Grand Am 3.4L cruise
hello everyone in iatn land. we have got an ever since today. we replaced ts switch & clockspring on this car 2 months ago. cust states cruise hasn't worked since. testing switch signals at module reveal no problems with switch, clockspring or wiring. looking ...		 View
2000 Saturn LS2 3.0L service engine soon
The service engine soon light is on, after diconecting the battery while cleaning the mass air sensor the light went out but still read the same codes and sfter about 6 restarts the light came back on. The car seems to run fine, smooth idle, good power but the... Trouble codes: P0171 (lean bank one), P0174 (lean bank two).		 View

Fixes & Summaries for GM
Fix/Summary Answers
1999 Buick LeSabre 3.8L Cuts out
WE ROAD TESTED THIS CAR WITH A SCOPE HOOKED UP TO THE MAP SENSOR AND WHILE MONITORING MY SIGNAL WE NOTICED WHEN IT CUT OUT IT WOULD DROP OUT .IT WOULD RESTART RIGHT AWAY AND THE SIGNAL WAS PRESENT.WE PUT A NEW MAP SENOR IN AND ITS BEEN ABOUT A WEEK AND ALL SEE...		 31
2002 Buick Rendezvous 3.4L ac compresor inop
i took the advice many of you gave me and recomended to the costumer to replace the BCM, but since we do not have the ability to flash the new BCM, we sent our cust to the dealer, and as of let have not heard back, we need to update and exspand our scanners, b...		 6
2001 Cadillac Catera 3.0L abs/tcs
The customer opted to not repair this vehicle. Most of the responses confirmed what I thought to be the case here and that's the EBTCM has a high failure rate in these cars. One of the responses suggested I try module masters for the replacement. I had alre...		 6
1991 Chevrolet Corvette 5.7L No Start
got 6 replies. Alva said to check inj relay behind battery. not sure what he meant by that. no such part as far as i can tell. David said he had a similair deal and it resulted in being a consolidated reman part issue. that was not the case here. Michael sugge... Trouble codes: 41 (hist dtc stored in ccm loss of ecm comm), 54 (hist dtc stored in ccm fuel enable failure).		 6
2001 Chevrolet Cavalier 2.2L Poor Idle Quality, Hesitation, Misfire
Thank you for all the suggestions, it appears this one may be fixed as it has not acted up for a while. Replace crankshaft sensor first and then ignition module. Thanks again Trouble codes: P301 (Random Misfire).		 13
2007 Chevrolet Express 6.0L Lighting
Thanks for the replies. I never did find the factory wiring. It looks like the factory setup uses a couple of relays also(which were not there) to power the turn signals and parking lights, so customer just opted to put in the aftermarket trailer wiring kit.		 2
1989 Oldsmobile Delta 88 3.8L engine
I’m really sorry to bother you for I’m 70 years old and I though I had a computer problem! My ex boss told his man to fix it and it took him three weeks to put in a lower control arm that I furnished. The engine was running OK but was pulling to the left. I di...		 14
1998 Oldsmobile Cutlass 3.1L Cuts out
Well thanks for all the help i tried everything and lost. new crank sensor comp. ign switch . coolant temp. and nothing same effect . win some lose some 		8
2001 Oldsmobile Alero 2.4L instrument cluster
After replacing BCM with no luck, we rechecked all powers and grounds to cluster and radio. Everything checked out fine voltage wise. I think our problem was amperage. We found a lot of moisture and green corrosion in the main fuse panel. Pulled fuse panel and...		 8
1988 Pontiac Firebird 5.0L Stall, timing won't set
I'm sorry, but I had to put this car on the back burner for a while. I have to close this post for now due to time allowances. I'll add the repair info when I get back on it. I tried another ecm with no changes.		 11
1996 Pontiac Grand Am 3.1L starter
I,m sorry I thought I closed this. I wanted to thank Glen for keeping me on track. I ran a jumper wire from the red wire going to the switch to the yellow wire going to netural saftey switch. The car cranked over. I didn't think the electrical part of the swi...		 21
2000 Saturn LS1 2.2L compressor fuel gauge
Thanks for the responses. I have recommended that the BCM be changed, based on current replies and results of archive searches with similar problems. No money right now so I will update when she has it done. Thanks again for your input!!!		 3
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