GM Automotive Technicians Technical Discussion and Fixes for Jan 25, 2006

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	Help Request	Answers
	1992 Buick Regal Gran Sport 3.8L Stall VIN: 2G4WF54L2N Customer states car intermittantly, is hard to start. Engine will start and stall. Sometimes it coughs in the intake and blows a vaccum line off. Replaced crank sensor with known good one, no change. All scan data w tech two, is normal. no codes. To me, it act...	View
	1999 Buick Century Custom 3.1L abs lite VIN: 2G4WS52M9X abs lite on code 1232 lf sensor open or short sets can duplicate by power braking and turning wheel current code statis will come on and off as code sets. have tested wires from sensor to module all ok ohm readings and ac readings same at sensor and at wiring ...	View
	1998 Cadillac Catera 3.0L Electronic VIN: W06VR52R3W hi guys, this caddy is not blowing any heat on the driverside. the passengerside is getting great heat. we cannot acess any body codes with our mt2500 or our genesis.i was told by a tech line to try and flush out the heater core and i did today. it made no di...	View
	1993 Chevrolet Cavalier RS 2.2L Cuts out VIN: 1G1JC1445P Originally this vehicle would run for a little while (5-10 min) and then get intermittent spark and then lose all spark. Now the vehicle has intermittent spark or no spark all of the time. The crank sensor has been replaced. Two different computers have been t...	View
	1993 Chevrolet Lumina Euro 3.1L Excessive Emissions VIN: 2G1WN54T9P Hi all! This wonderful piece came to our shop having not run for several years. First thing we replaced the ignition module for no spark. It kicked off and we were on our way. We replaced the coil for a cracked tower, the egr for cracked solenoid, and R&R'd th... Trouble codes: 43 (ESC module circuit - intermittant)	View
	1994 Chevrolet Caprice Classic 4.3L stumbles VIN: 1GBN52WXRR customer came in with complaint of engine misfire and MIL.Found defective distributor cap(wet).Gave it a good tune up.Cleared codes.Much better.There still is a intermittent stumble under light acceleration at 50 to 55 mph. Sounds and feels like the transmissi... Trouble codes: 0300 (random misfire)	View
	1997 Chevrolet K1500 Cheyenne 5.7L Excessive Emissions, Poor Idle Quality, Stall, Misfire, MIL Lamp on VIN: 2GCEK19R2V THANKS UP FRONT GUYS. THIS TRUCK CAME IN WITH THE COMPLAINT BEING IT WAS MELTING BATTERY CABLE! we found the starter drawing over 350 amps-replaced starter and repaired cables! know we have vehicle running and it was real rough and black smoking out the tailpi... Trouble codes: P300B (random missfire-)	View
	1999 Chevrolet K3500 6.5L MIL Lamp on, hard starting VIN: 1GCHK33FOX Hello all in iatn land; This vehicle is in with a hard starting/long cranking complaint PLUS the cruise control doesn't work. I drove the vehicle and it runs well enough after it gets running and pulled code P1216D. Problem is that MOD does not list that code ... Trouble codes: P1216	View
	2000 Chevrolet Tracker 2.0L belt VIN: 2CNBJ13C8Y The belts after 2-3 months begin squealing and show sigs of wear. Any idea what is causing problem. Second,when drivig over rough areas of roadway there is a continual squealing noise that comes from the passeger side. A metal on metal sound. The noise also oc...	View
	2001 Chevrolet Silverado 2500 6.0L battery indicator VIN: 1GCHK24U41 the truck came in with the voltage gauge jumping back and forth. with the volt meter hooked up to the battery it would jump from 12.9- 14.4 as fast as if you were flipping a switch. if you unplug the 4 wire connector on the back of the alternator and use a tes...	View
	2001 Chevrolet Impala LS 3.8L vats/bcm VIN: 2G1WH55K11 The car will not crank at times. Simple right. However, it will "not crank" with enough consistency to do any testing to see which component it is. This system does not use the chip in the key but rather the magnetic signal around the ignition switch. The valu...	View
	2002 Chevrolet Venture LS 3.4L noise on turns VIN: 1GNDX03E92 Ok this car was brought to us with a complaint of noise wile turning. It is hard to duplicate! You must be going slow wile turning almost to full lock to the right or left (like say driving thru a parking lot) The noise is quick it also vibrates wile it makes ...	View
	2003 Chevrolet Avalanche 1500 North Face 5.3L speedo VIN: 3GNEK13T53 Hey Guys, I have this Avalanche in for the speedo off 15 mph. It starts out at 15mph at idle and remains that much off during acceleration. All other gauges work perfectly. No codes were stored. Not sure what else to test? I have read alot about dash clusters ...	View
	1997 GMC K2500 Sierra SL 5.7L MIL Lamp on VIN: 1TGEK19R4W Have installed lpg system .Drives good for a week or so with service engine soon light on until it gets enough codes and then goes into limp mode.Have fitted emulators to o2 sensors. I have tried everything i can think of to stop this occuring. It is only when... Trouble codes: P0133, P0153, P0171, P0172, P0175	View
	2002 GMC Envoy SLE 4.2L 4x4 VIN: 1GKDT13S12 this vech will not engage 4wd in wet conditions. if you select 4wd on a dry day it will work. if you select 4wd on a wet day before you drive for the first time it will engage..i see that there are encoder issues on this site however i'm not sure this will sol...	View
	2003 GMC Sierra 2500 SLE 6.0L mode door VIN: 1GTHC23U23 Hi techs, I have this truck in the shop a few times .The heater cable keeps poping the springs like there is to much tension in the mode door. The heater box has been completly removed and made sure there is no binding or restriction in the mode door operation...	View
	1985 Oldsmobile 1985 3.8L oil pump tried 5 or 8 times to prime oil pump but every time it primes up it only lasts for a few moments then goes away any one have any new ideas on how to prime the oil pump on a 3.8 engine	View
	2000 Oldsmobile Alero GL 2.4L Cuts out VIN: 1G3NL52T7Y This vehicle cuts out at idle. Runs great all other times just at idle there is the problem. Of course you can fill the cutting out / jerking with the vehicle in gear. The vehicle never dies it just cuts out at idle. It will do this every 10 to 15 seconds as l...	View
	2003 Pontiac Vibe 1.8L Misfire VIN: 5Y2SL62873 has anyone seen misfire problems on pontiac vibes/ toyota matrix? this one came in for an obd emissions inspection. the mil was off but it failed because of the above codes. the customer hadn't noticed any running problems or misses, and we couldn't duplicate ... Trouble codes: P0300, P0301, P0302	View
	1996 Saturn SL2 1.9L Excessive Emissions, Surge VIN: 1G8ZK5272T this problem occur when the car is cold we have a long cranking time ,and a black smoke from the exhaust all the reading on the scanner seem to be ok no code good fuel press . i try a new map but same problem ,i sure that the car is flooded can you help me	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	1994 Buick Park Avenue 3.8L no power VIN: 1G4CW52L4R I would like to thank everyone for their replies for my problem 94 buick park ave. David [...] hit the nail on the head with a fuel pressure drop under full load on a road test. Pressure was 40lbs to start out and on a heavy accell pressure dropped t...	36
	1982 Cadillac Seville 4.1L door locks VIN: 1G6AS6985C 5 OF THE 6 REPLIES SAID SAID TO CHECK THE door lock switches causing voltage to intermitantly activate the relay one said check the ground circuit...this sounded reasonable to me so I ordered two new GM switches (including the euscheon) on line from O.E. PARTS...	6
	1988 Cadillac Seville 4.5L idles up and down VIN: 1G6KS5155J thanks John,that relearn works fine,and Todd and others,retrack,set voltage,then extend set voltage,then relearn and time the intervels,and have to move to drive then park and then ac on for 1 min,i thought I had toasted the ecm,thats why I keep my mouth shut ... Trouble codes: 22 (TPS open).	8
	1994 Cadillac DeVille Concours 4.6L failsafe VIN: 1G6KF52Y6R Stephen from Florida hit it right on the head, the solenoid screen popped out and this is what broke the solenoid. I don't know how I missed this, but it was very obvious when I removed the pan again. the fix is a kit that GM sells as a package including the t...	5
	2001 Cadillac DeVille DTS 4.6L traction control VIN: 1G6KF54931 The problem was in the third stop light, it is the LED type and worked just fine but had high resisatnce. spec is 390ohms + or - 10ohms we had 270k ohms, we put a 390 ohm resistor in place of light the problem is FIXED, new light is ordered, thanks to all that...	6
	1996 Chevrolet Tahoe LS 5.7L starter and flexplate teeth VIN: 1GNEK13R8T Thanks to all who responded to my problem with the Tahoe. Most of the people who responded mentioned the cap and rotor. Taking everyone's advice, I replaced the cap and rotor with the dealer's AC Delco cap and rotor.We also put in a new crank position sensor e...	18
	1998 Chevrolet C1500 Cheyenne 4.3L No Start VIN: 1GCEC14WOW First, I thank every body that replied to my post. I have a feeling that most that replied did not understand which system this is. This key does NOT have a transponder or a chip in it. It turns out that the Passlock module was the problem. It did not act like...	11
	1999 Chevrolet Express 2500 5.7L Water Pump VIN: 1GTHG35R5X I dont really know what to say, we put another water pump on the vehicle and all is well so far. There were a lot of responses regarding proper torque, threads, loctite, sealant, etc...I can assure you when we posted this help request, all the basics were chec...	10
	2001 Chevrolet Silverado 3500 8.1L gear select VIN: 1GCJK39GX1 Thank you for the replies. One had sent a list of TSBs and the the rest had said the range selector switch, or the PNP switch as some called it.Found multiple trannny codes as stated in the TSB # 03-07-30-11C.This switch is a link between the computer and tran...	12
	2003 Chevrolet Silverado 2500 6.0L Front Passenger Door VIN: 1GCHK23U83 Thanks for the replies. As it turns out it is a faulty PDM. Tried resetting by removing fuse and even disconnecting battery, no effect. Found TSB on problem thanks to Brian. Scheduled trip to dealer for repair. I wish I had a Tech 2, life might be easier. Than...	6
	1994 Oldsmobile 98 Regency 3.8L key security VIN: 1G3CX52L6R Thank you all very much for the very fast response, you were all faster than my snap on scanner,you all hit it dead on,must be a very common problem. Put in the resister from radio shack, after measuring the key pellet,now starts up without any problem. Thank ...	28
	1996 Oldsmobile Aurora 4.0L No Start VIN: 1G3GR62C3T Hi guys, I feel embarassed for writing this request after I sent request out all I could think of was the low fuel pressure.So being the weekend I took a mental break & put together a new stategy I completed a voltage drop test at fuel pump & had solid batt vo... Trouble codes: P0707, P0101.	3
	1999 Oldsmobile Intrigue GL 3.5L Balance Shaft VIN: 1G3WS52H1X Since there were no aftermarket bushings for the balance shaft, and none available from GM, two bronze bushings were made with an oversized OD and honed after installation to proper size for the balance shaft journals. The car has been on the road for almost a...	7
	1997 Other GM P-30 6.5L Excessive Emissions, Misfire VIN: 1GBKP32Y5V Thanks to all that responated. As it turns out most of you were right on the money. I was able to fix the problem by bumping up the pump timing. The bus now runs great and has been on the road for a few days now with no problems. Thanks again Tom	4
	1997 Pontiac Trans Sport 3.4L prnd321 The customer of the Transport decided that his PRNDL problem was'nt a big enough issue for him to spend any significant more money as the van needed other unrelated repairs. Thanks for the replies.	5

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