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Open Help Requests for GM
Help Request Answers
1996 Buick Century 3.1L Hesitation, Cuts out, high idle
I have a high idle speed that won't quit. Initially came in with dying problem. Fuel pump and filter fixed that. Then, I encountered the high idle speed. Customer was livid that I charged for work that didn't fix all his problems. I replaced the TPS, IAC, PCM(... Trouble codes: P0507 (Idle rpm too high).		 View
2002 Buick Rendezvous 3.4L gauges
Van came in with a compliant that her battery light comes on and lights go on and off. She says it worse when it rains. Also sometimes after the van is shut off it will not restart. She says the theft light comes on and if she disconnects the battery it will s...		 View
1991 Cadillac DeVille 4.9L oil pump?
This caddy came in for an oil change and after we changed the oil my lube tech says, Hey whats this red light mean? The oil light was glowing solid and the lifters were noisey,we loosened the oil filter about two turns, disabled the ignition,and cranked it. No...		 View
2003 Cadillac DeVille 4.6L MIL Lamp on
Last week I replaced a TPMS sensor on this Caddy, no problem there (except the tool to clear the TPMS monitor was $320). Customer called me up and said that his daughter left something on and the battery was DEAD. He jump started the car and the SES lamp was o... Trouble codes: P0601 (PCM checksum error).		 View
1989 Chevrolet Corvette 5.7L Unknown
We have a vette here that just doesn't want to stop.New pads and rotors twice,new booster...the pedal effort is exteremly high and the stopping distance is just too far.We put brake pressure gauges on one front one rear,1600 psi on the front,900 on the rear.In...		 View
1991 Chevrolet Lumina 3.1L Excessive Emissions, No Start, Poor Idle Quality, Surge, Cuts out, Stall, Misfire, Poor Fuel Economy
will not idle , off idle seems ok , if you rotate the key back just far enough to disengage the starter and hold it , it will run fine , but does not have power to all the sysytems in the car when you do this , i suspect ecm but not sure , have checked all the... Trouble codes: 45 (running rich).		 View
1996 Chevrolet Tahoe 5.7L Poor Idle Quality, Misfire, MIL Lamp on
Customer complaint of running rough.The ck engine light was on before the intake repair and after.I only scanned after repair,with a po300 since they were looking for a leak,coolant.Looking up misfire data #5 was misfiring,pulled plug black sutty deposits,comp... Trouble codes: PO161 (O2 heater bank 2 sensor 2), PO300 (Random Misfire).		 View
1997 Chevrolet Blazer 4.3L Fuel gauge
This vehicle came in with a main complaint of the fuel gauge flickering when the turn signal is on. It does not matter right or left. Also does it with the Hazards on. I noticed that the interior lights also flicker rythmic to turn signal. I hokked up a volt g...		 View
1997 Chevrolet Blazer 4.3L monitors not ready
have a blazer that will not pass state emission test because monitors show not ready. drive truck for 10 miles and all monitors show ready. turn truck off for two minutes and all monitors show not ready. comuter has good power and grounds. replaced computer an...		 View
2001 Chevrolet Express 5.7L Misfire
hello everyone,we have this van with a misfire count on cil#2 and #3,you can not feel the misfire but this way we can not get it trhu the aircare/smog test,i checked iatn and found a lot of info,tryed everything [we can think off],we installed a rebuild long b... Trouble codes: P1381 (mis fire- no comunication with brake controle module), P300 (misfire).		 View
2001 Chevrolet Express 4.3L Misfire, MIL Lamp on
We repaired an intake manifold coolant leak and also sold the cap, rotor, plugs and wires at the same time. The truck came back 2 days and 150 miles later running bad with a tip-in missfire off idle and 2 codes: P0300 Random Missfire and P0350 Crank Position S... Trouble codes: P0300 (random missfire).		 View
2002 Chevrolet TrailBlazer 4.2L Unknown
Hello, We have a Trailblazer that was towed in. Here is the customer's story: He drove home and parked in the driveway. Went to pull out the next morning and nothing happened. When he went to put it back into park to shut it off, he heard a grinding noise. He ...		 View
2003 Chevrolet Monte Carlo 3.4L Unknown
I have this 03 Monte Carlo that is starting to have some issues on our lot (we have had this one out front a couple months w/no problems).First the battery was going dead so we replaced the battery.Second the Ignition switch started acting up (electrical acces...		 View
2003 Chevrolet Express 4.3L No Start
Vehicle was towed in, battery tested bad, replaced battery, drove vehicle back to customer...next day customer calls and says it cranks, without starting. Towed in, found when cranking, it sounds like it's out of time, it cranks then grunts, then cranks, We re... Trouble codes: po300 (random misfire history not returned yet), po1629 (anti-theft history...not returned yet).		 View
2003 Chevrolet Impala 3.4L bpmv
Customer came in for brake inspection. After normal rear brake job (pads and rotors) customer was called letting him know car was finished. Customer tells me that after traction controlled acceleration twice this past winter ABS and trac light on. After turnin...		 View
2008 Chevrolet Cobalt 2.2L No Start
Well story begins with customer putting 2 gallons of diesel fuel in tank while refueling. They was afraid to drive it so the store owner recommended they bring it to us. Yes i know it being a 08 model with not even 5000 miles on it it should have went to deale... Trouble codes: Po230 (Fuel Pump Circuit Malfunction).		 View
2002 GMC Yukon 6.0L Ride Control
I'm not sure where to start on this one. Customer complained of the "Service Ride Control" light is on. I don't really know where to start on this one. Before I probe the wrong wires with my test probe, I just needed a little insight from you guys (and girls) ...		 View
1996 Pontiac Grand Am 3.1L ERLS fuse blows very intermittently
This vehicle arrived here 1 month ago with the Check Engine, Redrake lamp, ABS and TCS lamps on. I found seven codes in PCM (TCC and ATX solenoids, EGR, and EVap sol), and no communication with ABS/TCS. ERLS fuse was blown. Replacing fuse corrected the problem...		 View
1998 Pontiac Grand Am 2.4L leak
I have a coolant leak at the rear of head at no.4 piston.I can see the outlet tube and it don't look like its coming out there.Its coming out right under exhaust manifold. Has anyone seen this and can help me? Its a small drip not a big leak but has to be fixe...		 View
1993 Saturn SL2 1.9L Excessive Emissions
This car has me stumped. The O2 sensor pattern at 700 rpm idle is a cycling .3 to .8 volt pattern of 140 ms from bottom to bottom which I suspect to be a lean injector or two. The pattern at 15 mph is a dirty signal but is switching from rich to lean. At 25 mp...		 View

Fixes & Summaries for GM
Fix/Summary Answers
1995 Buick Park Avenue 3.8L Instrument cluster & HVAC
Thanks for all the replies. A new actuator fixed the passenger side heat issue, which you all suggested. The engine miss was definately a tune up issue. The customer said he had a tune, just didn't remember when. I should have caught on to that. I found 2 plug...		 5
1995 Chevrolet S10 Pickup 4.3L No Start
Thank you all for taking the time to reply. Many people thought maybe the distributor had been disturbed. Many thought maybe the catalytic converter was clogged, so did I but it was not. We checked the plugs when we ran the compression check prior to posting. ...		 22
1998 Chevrolet Astro 4.3L front driveshaft
Thanks to all for taking the time to help. I sent the astro down the highway without the driveshaft. It's already seen a couple hundred miles with no problems so I'm sure it will be fine. Thanks again Marty		 7
2000 Chevrolet Tracker 2.0L Oil Leak
Thanks for the responses. The second main seal fixed the problem I was just more careful when installing. I verified pcv and other oil leaks were not the problem as suggested. To answer my own question the tool from gm en-48108 while it seems to be an excellen...		 4
2002 Chevrolet Impala 3.4L MIL Lamp on
I appreciate everyone's input and help and apologize for the latness in responding to this problem. We ended up replacing the gas cap and the EVAP test passed. Although the gas cap passed under a normal test, cap must of been faulty. We waited a couple of week... Trouble codes: P0442 (p0440-), P0440.		 8
2004 Chevrolet Avalanche 5.3L Hesitation, Surge, Cuts out
Good morning, I want to thank you all for your help and let you know what we found that fixed the truck. The close inspection of the wiring for the fuel system before saying the pump maybe bad showed a oil pressure sensor in the system. After unplugging it and...		 6
1993 GMC Pickup 5.7L Cuts out, Stall
Fix ended up be an O2 sensor failure. Sensor was switching between .4 to .8 via the scanner reading, but when I tested it directly it was pegged at 1.1v. 		11
2001 Oldsmobile Alero 3.4L MIL Lamp on
Thanks for all of your help reflashing the pcm fixed this car. next time I see this problem we will replace the egr and reflash the pcm Trouble codes: p1404 (egr closed possition performance).		 15
2000 Pontiac Grand Am 3.4L Misfire, MIL Lamp on
Iatn post was posted prior to vehicle arrival since this car has been a long standing headache here. Codes always have been P0300 misfire, this time new code P0206 injector 6 control circuit. Injectors are not easily accessible on this model. Connected noide l... Trouble codes: p0300 (misfire).		 4
2001 Pontiac Grand Prix 3.1L Hesitation, Surge, Cuts out
Thanks to everyone..Max from Ohio sent me searching.After a lot of checking I finally caught the TRAC light would come on once in a while when this happened.Took the fuse for the abs out over nite and it hasn,t done it since I reinstalled it.I assume at some p...		 17
1999 Saturn SC2 1.9L Misfire
Thanks for all the help. Sorry it took so long to close this post. I wanted to wait acouple of days after the cusromer picked up the car to make sure it was fixed. I went back and started to move things around like the coil packs, injectors and spark plugs. Af... Trouble codes: PO302 (Cylinder 2 Misfire detected).		 6
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