GM Automotive Technicians Technical Discussion and Fixes for Jun 16, 2009

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Open Help Requests for GM

	Help Request	Answers
	1991 Buick Regal 3.8L Poor Idle Quality, Surge, Stall The complaint is that sometimes turning into a parking lot it will stall. I could not get it to stall but the idle is rough like it is loading up with fuel. The fuel pressure is good 42 p.s.i. I scanned for codes and it had a code 13 (O2 sensor circut). At idl... Trouble codes: 13 (O2 sensor)	View
	1996 Buick Roadmaster Collector's Edition 5.7L MIL Lamp on VIN: 1G4BT52P2T Well here is another one, customer came in and asked us to replace his egr valve with a new valve he bought. replaced valve & customer came back next day with check engine light on for egr code (P0400). Now customer would like us to diagnose check engine light... Trouble codes: P0400 (egr system malfunction)	View
	1997 Cadillac DeVille 4.6L pcm VIN: 1G6KD54Y1V Towed in with crank no start. Security system malfunction displayed on IPC: "Theft system problem, car may not restart". Did some research and concluded that since the engine cranks there is not a problem with the VATS. Tried to pull codes from the PCM but the...	View
	2001 Cadillac DeVille DTS 4.6L radio will not turn on VIN: 1G6KF57961 Reprogrammed the existing PCM for this DeVille in the vehicle. Use approved SMP IFlash J2534 tool and TIS2000 programming. Updated Cal ID [...]. After reprogramming, the radio will not respond to the on/off on the touch screen. Touch screen is illuminated, ...	View
	2007 Cadillac Escalade ESV 6.2L temp door VIN: 1GYFK668X7 This Caddy has a left side temp door that is intermittantly sticking. With the actuator removed you can only move the door about half travel. You can get it freed up and it will work ok for a while only to stick again. I would like to give the customer a bette...	View
	1988 Chevrolet Corsica 2.0L No Start VIN: 1G1LT5118J howdy, this car was towed in for a cranks but wont run complaint, the customer had replaced the igntion module and crank sensor a couple of weeks earlier (unknown what brand) for the same complaint,when i first got in it to pull it in the yard it started easil...	View
	1997 Chevrolet K2500 Cheyenne 6.5L Poor Idle Quality, Cuts out VIN: 1GCGK29F4V We usually work on german cars, but some of you may have more info on this problem. The truck starts and runs fine when cold, however after warming up and been driven for a while, it idles rough. It will set following fault codes P1214 Injection timing offset,... Trouble codes: P0216 (Injection timing control circuit), P1214 (Injection pump offset), P0236 (TC boost system)	View
	2003 Chevrolet Astro 4.3L door locks, dome lamp VIN: 1GNEL19X33 Just wondered if anyone has encountered this before I begin diagnostics, no BCM or any other stored codes. While driving, usually over bumps, door locks attempt to re-lock, and dome lamp comes on, sounds like poor switch contact at one of the doors, any ideas ...	View
	2004 Chevrolet Impala 3.4L No Start VIN: 2G1WF52E44 This vehicle is a no start anytime - Have checked all powers & grounds - labscoped crank and cam sensors signals at PCM and they are good - replace PCM thinking it had a bad circuit internally and had it programmed by the dealer= still no start - tested igniti...	View
	2006 Chevrolet HHR LT 2.2L MIL Lamp on, Reduced Power VIN: 3GNDA23D56 The code P2128 and reduced power displayed in the driver information center sets intermittantly. Freeze frame showed fault set at idle and at operating temperature. Cleared codes and can't duplicate problem or get code to reset. Watched data stream with my Mod... Trouble codes: P2128 (APP Sensor 2 Circuit High)	View
	2007 Chevrolet Express 2500 4.8L Hydro Boost? VIN: 1GCGG25V87 Hey guys, thanks in advance for your help. I have a 2007 Chevy Express Van I would like an opinion on. The customer complained of a front end wobble after long drives. Drove the vehicle and found all four brakes stuck on causing overheating. By the time I got ...	View
	2009 GMC Sierra 1500 SLE 5.3L brake controller VIN: 1GTEK29J09 I was wondering if there are any dealer techs out there who have installed a trailer brake controller on a 2009 yet. I cannot locate the harness to splice into. I checked under the left side of the dash and near the under-hood fuse block. This truck is not equ...	View
	1988 Oldsmobile Cutlass Ciera Brougham 2.8L Excessive Emissions, Poor Idle Quality, Hesitation, Cuts out, Stall VIN: 2G3AM51W9J Here we go again, This is a stumper for us. This car was brought in with low power intermintent dying, missing, rough idle, We started with the obvoius. We checked the TPS and replaced it, slight change, we've replaced over the past several weeks, TPS, IAC, Cr...	View
	1996 Oldsmobile Cutlass Supreme SL 3.1L tcc VIN: 1G3WH52MXT vehicle came in for a poor fuel economy was diagnosed by another tech for tcc not applying. tech sold valve body replacment which included tcc and all shift solenoids. replaced valve body and now have tcc apply when going into second gear. am able to command i...	View
	1999 Oldsmobile Cutlass GL 3.1L Poor Idle Quality, Surge, Stall VIN: 1G3NB52M5X Strange one here. When vehicle is started engine will idle at about 750 RPM for a few seconds and then start surging not bad (100 to 150 RPMs)but very noticeable. What makes this bad is that it happens at about the same time you would normally put can in gear....	View
	2002 Oldsmobile Bravada 4.2L Poor Idle Quality, Stall VIN: 1GHDT13S32 I have a Olds Bravada with 4.2. On cold start, will start, run for 2-3 seconds and stall. It will do this 2 times and then start and run fine. No codes have ever set. I have monitored fuel pressure (52PSI), tried a different throttle assy., used a resistor for...	View
	2003 Saturn Vue 3.0L Mechanical VIN: 5GZCZ63B13 Customer came in with excessive valve train noise found a post that said to change the oil, if that didn't help check valve timing,it is ok also checked oil pressure 70lbs any help would be appreciated before I start taking it apart ,Thanks in advance	View
	2003 Saturn Ion-1 2.2L Lighting VIN: 1G8AF52F83 This vehicle has a fault in the right front turn signal system. I get a code B3949 indicating open circuit, short to ground or short to power. The right rear bulb flashes but fast. No flashing to the right front. The bulb is good as I can input a signal and it...	View
	2006 Saturn Ion-2 2.2L MIL Lamp on VIN: 1G8AM15F66 This car came in after she drove through heavy rain. The car had sucked up water from the fender area into the engine. It still ran but the oil was like choclate milk. Water had gotten in the floor board about half an inch when she opened the door. The compute...	View
	2006 Saturn Ion-2 2.2L speedo VIN: 1G8AW12FX5 code lost communication to trans module need to know if this a program problem or someting i am getting out of fuse box	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	2002 Buick Rendezvous CXL 3.4L Unknown VIN: 3G5DB03E73 Thanks for the help on this one. This one was tough because customer was waiting the whole time. We wont be getting a chance to fix this one, but what I found was the torque converter is causing the noise, shudder. we noticed when the noise is present slip spe...	6
	2005 Cadillac Escalade 5.3L No Start VIN: 1GYEK63N55 Hi everybody, thanks for all the helps i've received but the key seemed to be not the original one for the car it has been cut locally but below is the procedure that i received how to program it: 1 Turn ON the ignition, with the engine OFF. Attempt to start...	7
	1993 Chevrolet Blazer Cheyenne 5.7L Surge, Poor Fuel Economy, MIL Lamp on VIN: 1GNEK18K6P Seems this beast had two problems. After talking again with customer he said it has been an ongoing thing and was getting worse. The problems were a broken base gasket under the TBI. Also found the magnet cracked in the distributor. So by replacing both the ... Trouble codes: 43 (ESC System fault).	21
	1994 Chevrolet C1500 Suburban Silverado 5.7L piston ring VIN: 1GNEC16KXR Howdy boys n girls, Well, the old sub is still shakin, got a lot of supporting replies stating that the cleaning media should not have damaged anything, and maybe it was just coincedental, my tech did say that is was shaking when he pulled it in for repairs. A...	26
	1995 Chevrolet Lumina 3.1L No Fan Actuation VIN: 2G1WL52MXS First off, a sincere thank you to everyone that so prompltly replied. The concensus of experience is that the fans should be commanded on somewhere between 220-230 degrees F. In my haste to post the question, I failed to mention that the fans do cycle when A...	17
	2000 Chevrolet Malibu LS 3.1L Surge, Stall VIN: 1G1NE52J5Y Thank you all. Ricardo was right,it was the fuel pressure regulator.the customer brought the car back 4 days later running much worse.regulator spewing fuel.the vacuum nipple was loose on my smoke test and relaced when first serviceing. did not appear to have ...	8
	2001 Chevrolet Silverado 2500 HD LS 6.0L unsupported systems VIN: 1GCHK23U51 Let's say no I haven't "fixed" this vehicle. But with tech help, I got fixed. The truck has no door label on it and my guess was that it is under 8600 lbs. WHOOPS!! Nevertheless, this was a great learning experience to be confronted with. I will not b... Trouble codes: N/A.	7
	2001 Chevrolet Suburban 1500 5.3L power steering VIN: 1GNFK1GT91 well thanks for all the replies. we ended up getting back what we thought was the original pump from napa, installed and found they had sent us back the wrong one, the one we recieved had a snapped shaft and they were unable to locate the original pump. doing...	15
	2003 Chevrolet Avalanche 1500 North Face 5.3L Compressor VIN: 3GNEK13T33 Thank you all for you help. I found the problem in the wiring to the ambient air temp sensor. There was a section of wire that the local Chevy dealer had replaced about year ago that was not repaired correctly. Replaced bad portion of harness and all is wel...	4
	2003 Chevrolet Trailblazer North Face 4.2L security lamp VIN: 1GNET16S03 I researched ALL DATA and found this information. It said if the light is on steady, (Which mine is, not flashing). It means the ignition switch was tampered with and turned without turning the tumbler for the passkey to know if the correct key was used. I did...	6
	2003 Chevrolet Silverado 2500 HD 6.6L Poor Fuel Economy VIN: 1GCHK23163 sent vehicle to dealer and found nothing from dealer. they said everything is normal according to them.	5
	1999 GMC Savana 1500 5.0L idle high 2500 rpm VIN: 1GTFG15MOX Thanks to all after looking over my work and could not fine anyting wrong with this I guess isc 0 kind a threw me off thinking had a vacuum leak. Installed new isc now idle after testing drive make sure everything now f-c--- thing know like main bearing spun....	2
	2004 GMC Sierra 1500 5.3L valve train VIN: 2GTEK13T75 First off let me thank everyone that replied.after thinking about the problem i came to the conclusion that i might be getting air into the system,in order to check this out,i overfilled the crankcase with oil in order to bring the oil level over the pickup tu...	10
	1999 Oldsmobile Alero GL 3.4L MIL Lamp on VIN: 1G33NL12EX wire under IAT connector broken. replaced plug and all is well thanks to all that helped Trouble codes: P0113.	9
	1998 Pontiac Grand Prix GT 3.8L blower motor VIN: 1G2WP12K1W I received just a few responses but all were right on the ball. The electrical part of the ignition switch was bad. Everything went smoothly but I did have to buy an e4 torx socket ($4.00) and it was a little of a pain to change but all is well now. Thanks aga...	6
	1997 Saturn SL2 1.9L Hesitation, Cuts out, Stall VIN: 1G8ZK5274V well we finally broke down and took this to one of our dealer buddies who scanned the vehicle with gm's tech one scanner. The tech one will display a value for knock retard.Our snap-on modis does not show this value. our saturn had a value of-18 to-34 knock re... Trouble codes: P1599.	8
	2003 Saturn Ion-2 2.2L Poor Idle Quality, MIL Lamp on VIN: 1G8AJ52F83 THANX FOR THE TWO REPLIES--WE ENDED UP REPLACING THE INTAKE GASKET- FOR SOME REASON IT WAS LEAKING AIR CAUSING A FALSE READING-O2 SENSOR WAS CONFUSED-AFTER THAT THE O2 WAS RESPONDING WITH NORMAL READINGS-VEHICLE RAN GREAT-THANX BRIAN Trouble codes: P0130 (o2 sensor fault-bank one sensor one), P1133 (ho2s bank one sensor one-not switching).	2

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