GM Automotive Technicians Technical Discussion and Fixes for Jan 29, 2007

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Open Help Requests for GM

	Help Request	Answers
	1998 Cadillac DeVille 4.6L Poor Idle Quality, MIL Lamp on, Excessive High Idle VIN: 1G6KD54Y5W Hello I hav e atough one here. I have searched the IATN Knowledge Base and did not find anything related. Car came to me on a trailer. Upon start up idle races and surges(guessing about 3500 to 5000 RPM. When you put it into drive it races at a higher, but, st... Trouble codes: P0101 (freeze frame), P1571 (freeze frame), P0121 (freeze frame), P0101 (freeze frame)	View
	1999 Cadillac DeVille 4.6L Steering VIN: 1G6KD54Y4X The car's steering system light is lit on the dash board, and no codes are stored. The steering seems alittle tight. BEFORE the light came on we: replaced the battery, it had a bad cell and the changed the alternator (a/c delco)it was not charging; car was to...	View
	1960 Chevrolet Impala 283CID wipers, washer VIN: 01819K1492 This is the second wiper motor from Ecklers late great, the first motor worked 5 minutes and something let loose inside, sent it back (havnt seen credit yet), bought one more that was working great, had wipers and squirters working, then out of nowhere it quit...	View
	1992 Chevrolet Lumina APV 3.1L No Start, Stall VIN: 1GNDUD6D6N Van towed in, starts and runs, very rich, no codes. Engine stalls, has spark no injector pulse, has power to injector no pulse. No RPM signal on scan tool.	View
	1998 Chevrolet Prizm 1.8L drl control module VIN: 1Y1SK5283W Thanks for checking this one out (again!). We certainly thought we had it tackled last time but it is back again with another module cooked!The pins in module (daytime running lamp and control module)that seem to be problem areas are pins 16, 17 and 19. It loo...	View
	2000 Chevrolet K2500 7.4L brake lights VIN: 1GCGK24J7Y we were told that the brake lights starting to stay on all the time after the trans was rebuilt. if you turn the dimmer switch on, the brake lights shut off. then if you hit the brake the lights blink and then the fuse blows. if i ground the gray wire at the d...	View
	2001 Chevrolet Express 3500 5.7L Misfire VIN: R911190751 after tune up van came back with cylinder misfire. we checked the vent holes in dist. replaced spider injectors with updated spider.checked fuel pressure 55 psi. #3 cylinder is missing the most but 2,4,5,6,7 are also missing.at an idle all is well and under ha... Trouble codes: 0300 (cylinder misfire)	View
	2003 Chevrolet w5500 .0L exhaust brake Don't do much diesel work, but occasionally have a brain freeze.This is a 2003 w5500 chev truck but with a 4 cylinder isuzu diesel engine.It came in with a noise like aq huge vacuum leak coming from exhaust brake on exhaust pipe.Ordered and installed new unit ...	View
	2004 Chevrolet Silverado 1500 4.8L Brake VIN: 1GCEC14V84 The guy who drives this truck has a point,you have to put your foot into it pretty hard to get a normal stop.Ive worked on and driven a bunch of these trucks and this one will not stop as quickly.He tells me its been like this since new and up until the point ...	View
	2004 Chevrolet Malibu 2.2L fuel pump i am wondering if a remote starter will bypass the theft deterent system even if the ighition switch is faulty(i have had to relearn ignition switch twice)somehow it loses memory .or is there some other reason the switch will lose its mem.	View
	2005 Chevrolet Impala 3.4L ims VIN: 2G1WF52EX5 Hello all, I have this 05 impala no start, in following trouble code diag on alldata and useing tech2 I have found the IMS to be reading incorrectly in park, trouble tree had me disconect AT 20 pin connector at trans all were reading hi as they should next ste...	View
	2002 GMC Envoy SLE 4.2L engine VIN: 1GKDT13S32 first time user we have a 02 gmc envoy with some top end noise hot or cold. i am not sure if it is the lash adjusters, over head cam, or rockers. any one have any idear or seen this problem.	View
	2003 GMC Sierra 2500 HD SLE 6.6L Alternator VIN: 1GTHK23173 Vehicle came in with battery light on, "no battery charging" message on dash. Tested for output, found no alternator output. Scanned OBD, found code p0621 "gen L terminal fault. Figured the alernator was bad, so got another one and installed it, still no charg...	View
	2001 Oldsmobile Silhouette Premiere 3.4L defrosters VIN: 1GHDX03E41 Hello, I am having trouble with the defrosters on this van. It seems to steam up the windows. I replaced the heater core, because it seemed something was on the windows, but it did not help. I saw no sign that the old core was bad. When leaving the garage ...	View
	1991 Pontiac Grand Am LE 2.3L ecm and injectors VIN: 1G2NE54D7M Hey guys I had a customer pull this car in, He said it has sat for a year and now won't start, I found a bad ignition module. Did not fix it. Then I hooked up my scanner and had no communication and found a burn fusable link. Thats when he tells me that he had...	View
	1999 Pontiac Grand Am SE 3.4L Antitheft/Airbag/Trans VIN: 1GZNW52MZV Hi everyone, ive got somewhat of an odd problem here. This Grand Am came in with a start and immidiate stall. The antitheft was enabled and the car wouldnt start. While inspecting the car I unplugged the 3 wire connecter at the ign switch to see if it was send...	View
	2000 Pontiac Grand Am SE 2.4L brake lights VIN: 1G2NF52T6Y have unplugged all related switches and computers along with relays for DRL. if you turn the park or headlights on the brake lights come on even the high light(third light). I also unplugged the tail light assembly on the left and right with no change. the hig...	View
	2001 Pontiac Grand Am SE 2.4L Poor Idle Quality, Hesitation, Cuts out, Misfire, MIL Lamp on VIN: 1G2NF52T71 I have this Grand AM that has had a tune-up with OE parts and fuel pump and filter replaced. The problem is that it has a constant lean run condition with trouble code P0171. If I remove a vacuum line and try to lean it out further the 02 sensor volts climb to... Trouble codes: P0171 (Lean Run Condition)	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	2003 Buick Rendezvous CX 3.4L abs VIN: 3G5DAO3E73 We found a suspect section of harness about 6 inches from the L/front w/speed connector-the insulation was fine but when we pulled on the wire from both sides you could feel it stretch.At this point we cut in and found that 80% of the strands were broken.To pr...	8
	1986 Chevrolet C10 Custom 5.0L Front brakes VIN: 2GCDC14H0G Hi, thanks for all the help. The customer hasn't returned with the vehicle. He doesn't drive it much in the winter. The consensus seems to be that it's either the control arm bushings loose, causing the wheel to lurch when the brakes are applied, or else the c...	43
	1990 Chevrolet Corvette 5.7L horn VIN: 1G1YY3389L Thank you, all replies contained useful information. However, Tim's reply was most useful in this case. Test at the turn signal switch at the base of the steering column. Ground the wire that leads to the horn button. If the horns work, then the problem is in ...	7
	1992 Chevrolet G30 Chevy Van 5.7L brakes VIN: 2GDHG31K9N Thanks to all for your ideas and help. I was unable to duplicate issue so I could not verify any repair. customer took it to dealer to see if they can help.	13
	1995 Chevrolet Blazer 4.3L Excessive Emissions, Poor Idle Quality, Hesitation, Misfire VIN: 1GNCT18WXS thanks to the 9 replies we hadon this vehicle. a couple of you hit it correctly. the fuel pressure regulator was leaking and it apparently feeds directly into the #2poppet line. we changed the regulator and the o2 sensor and it runs great again. thanks again f... Trouble codes: P0300, P0133, P0134, P1133.	9
	1997 Chevrolet Blazer 4.3L transfer case VIN: 1GNDT13WXV Fixed it. The problem was a wire shorted to ground. The brown/white wire between c106 and the encoder motor was pinched between the left inner fender and a mounting tab that is welded to the fire wall. This is located directly below the wiper motor about six i...	16
	1999 Chevrolet Metro LSi 1.3L Unknown VIN: 2C1MR222XX turned out to be the cat. i did the lick and stick test and the o2 sensor does change. I guess the o2 stays at 1.25 volt at idle dont see that every day. thanks	3
	2003 Chevrolet Malibu 3.1L No Start VIN: 1G1ND52J63 The vehicle did not return and I was not able to duplicate the no start when it was here. If I hear of anything regarding the problem I will post an update. Info that was sent to me varied. Some said to disrequard the U1000 code. One said to try a new key. Joe... Trouble codes: U1000 (State of module health).	11
	2005 Chevrolet Malibu 2.2L mil VIN: 1G1ZS52F95 reflash the computer and problem went away thats for all the help	9
	1995 GMC Jimmy 4.3L 4wd VIN: 1GKDTI3W9S Hi Guys Thanks for all the help on my 95 jimmy I checked everything & found the motor on the trasfer case was not turning far enough to engage the 4wd, put a used motor on & the frt shaft engaged then we had trouble with the frt diff not engaging it was a faul...	15
	1995 GMC K2500 Sierra SL 6.5L No Start VIN: 1GTGK29F0S thanks for all the replies, unfortutnately this customer is very impatient and doesn't understand that it will take time for us to find this intermittent problem. i am very sorry that i could not find a fix for this and if it ever comes back again i will reply...	12
	1995 GMC Jimmy 4.3L Front Diff VIN: 1GKDT13W75 THANK every one for your helpfull replies. After checking and rechecking and driving endlessly, I did find a very small vacuumn leak in one of the hoses. It never acted up on me. But I think this was the problem. If it comes back I will let ya'all know. Thanks...	6
	1998 GMC Jimmy Envoy 4.3L flasher VIN: 1GKDT13WXW Thanks for the support. Majority of the replies indicate the $250 turn signal switch. Customer has declined continuing with the repair, instead staying with the $1.50 rag and rubber band rap previously installed. Thanks again for help	30
	2006 Hummer H3 3.5L No Start VIN: 5GTDN13656 Hi, all members: Many thanks for those replies. As most of you suggest I replaced the ignition switch and now I am sure the problem is solved.	5
	1983 Other GM semi truck 700CID Shift Valve I removed the shift valve from the valve body and found a small piece of the PTO gear had found its way into the wrong place, causing the 'binding' feeling. After making sure that there were no more pieces in there I replaced the shift valve and all is working...	2
	1998 Pontiac Firebird Firehawk 5.7L MIL Lamp on VIN: 2G2FV22G4W We found a small piece of debris in the check valve on the passenger side that was keeping it closed apparently causing all the air to be diverted to the driver side setting the code. Once it was removed we haven't seen the problem return. Trouble codes: P1415 (secondary air injection bank one malfunction).	8
	2000 Pontiac Grand Prix GTP 3.8L converter VIN: 1G2WR5217Y Thanks for the repies. The vehicle is coming back this week and I received one reply relating to my problem. That is to check the wiring harness near the trans for rubbing through. The other replies were mechanical and this is an electrical problem.	5
	2003 Pontiac Sunfire SE 2.2L hvac VIN: 1G2JB12F33 Sorry abuout the delay, but we were waiting for parts. The fix is to replace the heater box, the new one is quite different and works perfect. thanks for the help Jeff	3
	2004 Saturn Vue 3.5L MIL Lamp on VIN: 5GZCZ53444 Thanks to those that responded,sorry it has taken sooo long to post,i was giving this one some time to prove itself.Well,after 4000 miles,i think we can call it a fix.The responses with reference to the saturn repair bulletin were riteon.After much diagnosis a... Trouble codes: P0300 (Random misfire--- all cylinders).	5

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