GM Automotive Technicians Technical Discussion and Fixes for Apr 5, 2006

Join Now

Prev	Professional Automotive Repair Technical Discussions for April 5, 2006 International Automotive Technicians' Network (iATN) - Members Only	Next
(Also Available: All, Asian, Chrysler, European, Ford, GM.)
Vehicle Owners: If you are seeking an automotive repair professional to service your vehicle, visit the iATN Repair Shop Finder.

Open Help Requests for GM

	Help Request	Answers
	1998 Buick Park Avenue 3.8L cruise control VIN: 1G4CW52K3W Cruise control light will come on. If driving on a flat level everything works fine. As soon as car starts to pull any kind of grade the cruise control light goes out and you can hear the accelerator pedal snap back. Checked all wiring to servo unit. Replaced ...	View
	2002 Buick Regal LS 3.8L MIL Lamp on, PO420 VIN: 2G4WB55KX2 This vehicle came to me with a hole burned through the intake phlenum and antifreeze in the cylinders. I replaced the Phlenum and cleaned up the cylinders. upon starting the vehicle discovered the starter was also bad. Replaced starter. After test drivining th... Trouble codes: P0420	View
	1991 Cadillac DeVille 4.9L Car accellarates VIN: 1G6CD5387N Thanks to all who take the time to reply. Customer states that the car will accellerate on it's own while driving with the cruise control off. He says the engine will race when stopped and in park. These conditions stop after the cars warms up. Problem is inte...	View
	1992 Cadillac DeVille 4.9L Surge, Stall VIN: 1GCD53B7N4 hey guys need a little help, not to many of these old caddys left but i got one. about once every two or three days this car will idle rough and stall. it will always restart. the iac motor will go nuts trying to keep the motor running. replaced map but didn't... Trouble codes: 30 (iac), 31 (map sensor), 74 (mat sensor)	View
	1988 Chevrolet Caprice 5.0L Hesitation, Cuts out, Stall, MIL Lamp on VIN: 1G1BU51H8H After driving this car a short distance the check engine light will come on. At this time when you try to accel. the engine hesitates, and bakefires through the carb, sometimes it will stall. This happens temp. then the engine runs fine and the light goes off.... Trouble codes: 43 (ESC volt low)	View
	1992 Chevrolet Cavalier RS 2.2L No Start, Cuts out VIN: 1G1JC5448N I have an intermintant die out/no start problem. Car has spark but no injector pulse. Fuel pump is oppereating properly, good pressure, cycles on when engin cranked. All four injectors ohm out to 12.2 ohms each. I have good ground and hots at ECM. Checked for ...	View
	1994 Chevrolet K2500 Cheyenne 5.7L all shifts VIN: 1GCGK24K7R Fellow techs, need help on this 94 pickup. Origianal complaint was harsh shifting. Customer stated that at first it only did it when it was in four wheel drive, but now it does it all the time. I scanned the vehicle and found code 73 (force motor current probl...	View
	1998 Chevrolet K2500 Cheyenne 5.7L fuel gauge VIN: 1GCGK24R6W Fuel gauge pegs full when first started, then seems to read a correct reading, but needle quivers and then jerks to a 1/4 tank reading higher or lower, then back to original reading and quivering. Fuel tank seems to get sucked in while driving and then pops wh...	View
	1998 Chevrolet C2500 Suburban 7.4L rear axle seals VIN: 3GNGC26J8W same	View
	1998 Chevrolet K3500 Cheyenne 6.5L Front end VIN: 1GCHK39F0W Hey guys, we have a wierd one here. The customer brought this truck in for a front wheel alignment complaining that it was shaking. I explained that an alignment wouldn't typically fix a shake but he said he wanted the alignment anyways due to slight tire wea...	View
	1999 Chevrolet K1500 Suburban 5.7L MIL Lamp on VIN: 1GNFK16RNX Truck came in with MIL ON, found above codes, cleared and only ones that came back were for Map low voltage, datastream confirmed voltage of 1.9V KOEO, sometimes be as low as .2V, doesn't seem to matter if vehicle is running or not. 5V reference to sensor good... Trouble codes: P0107, P0108, P1106, P1107, P0404, P0101	View
	1999 Chevrolet Blazer 4.3L 4x4 VIN: 1GNCT18W2X Hello When this vehicle came in it stayed in 2wd all the time and when started the tccm would click twice also the lights on the 4x4 switches would light up for about 1/10 of a sec. When vac is applied direct it would engage front diff.Now when I disconected w...	View
	1999 Chevrolet Tahoe LS 5.7L Rear differential VIN: 1GNEK13R6X We have been blessed with this 1999 Chevy Tahoe that feels and sounds like the rear end is twisting just at the end of a stop and then moving again as you take off. This is under slow to normal acceloration and if you do not make a complete stop the noise and ...	View
	2000 Chevrolet Cavalier 2.2L MIL Lamp on VIN: 1G1JC1245Y fellow techs. i have replaced converter 2 times , once with a universal converter, then with a (better) o.e. style aftermarket converter. after second converter, i started thinking maybe the post o2 sensor was giving it a false signal, so i replaced that. it t... Trouble codes: P0420	View
	2000 Chevrolet Tahoe 5.7L 2-3 shift VIN: 12CSERSDN2 if ran to 40mph and mill is reset, vehicle runs perfect...but when brought to 0mph and accelerated at 18mph it shifts, 30-35 no shift...then you get mill with po758...now this is wierd if you activate 1=4 sol u see power then ground(comand)on 2-3 ground all th...	View
	2000 Chevrolet Monte Carlo SS 3.8L TCC SLIP (RPM) :300 to 1000 normal spec +254 to - VIN: 2G1WXJ2K4Y Hi When the car get 55Mph and I did push accelerator pedal 1/4 of total distance. Engine Rpm oscilated from 1800 rpm to 2200 rpm.It last 3 to 6 seg. Engine data Load 70% map 4.0 volts TPS 1.21 volts Transmission Data TCC slip (RPM) 300 to 1000 TCC duty c...	View
	2004 Chevrolet Silverado 1500 4.3L fuel leak VIN: 1GCEC14X64 vehicle came in with smell of gas and a check engine light-found gas smell heavy under hood removed injector harness at spider found fuel leaking up thru injectors-i have heard of this before and have heard of fuel soaking thru wiring harness-i am unable to fi... Trouble codes: P0300	View
	2004 Chevrolet Aveo 1.6L Engine VIN: KL1TJ52024 Car came in on the hook because it stalled on the highway. When it came in it would start and then die. Pulled in the shop for diagnostics and it wouldn't start at all. Diagnostics showed a bad ECM (lost sensor ground) so I replaced it but that put us back to ...	View
	1996 Geo Metro 1.3L No Start VIN: 2CIM5292T6 this vehicle came in as a no start, upon initial inspection, we thought it was a timing belt. cranked w/ no compression. we removed the timimg cover , the belt was fine and all marks lined up. we removed the valve cover and inspected the cam and dist. all ok, ...	View
	2001 Geo PRIZM 1.8L MIL Lamp on VIN: 1YSK52851Z DTC P1349, Intake Camshaft (CMP) Position System code occurs intermittently always around 30-40 mph usually 35-45% throttle. Vehicle has new CMP actuator and we tested it on vehicle w resistance test OK and applied current causing engine to stumble and stall a... Trouble codes: P1349 (intake camshaft position cmp system)	View
	1995 GMC Jimmy SL 4.3L No Start, Hesitation, Cuts out VIN: 1GKDT13W1S hi. i have a 1995 gmc jimmy that keeps burning ignition coils out. When i got the vehicle it had been sitting for about 6 months and the heads had already been done but the car had an ignition miss feel to it. The first thing i did was clean out the carbon bui...	View
	1995 GMC K2500 Sierra SL 5.7L Hesitation, Surge, Stall, Low Power VIN: 1GTGK24K1S This vehicle has the whole shop at wits end. Intermittantly it will bog down and loose power. When it does if you let off the gas and then peg it the engine will begin to run normally about 70% of the time, the other 30% it will stall and then restart immediat...	View
	1995 Oldsmobile 88 Royale 3.8L Cruise Control VIN: 1G3HN52K8S Okay this should be a good one. Cruise control is inop. Tested all inputs/outputs, vacuum signal to servo and switch functions. All switches and inputs working on scan tool data also expect for "cruise control speed". This reads 0 mph. The speedometer has alwa...	View
	2000 Pontiac Bonneville SSEi 3.8L Radio inop VIN: 1G2HZ5410Y We replaced the intake gaskets on this car to repair a coolant leak. When we were done and reconnected the battery, the Bose Radio/ C-D/ Cassette displayed "CALIBRATE". The display worked okay, volume, channel, equalizer controls, all show the proper icons and...	View
	2000 Saturn LS2 3.0L wipers VIN: 1G8JW52R7Y on delay the wipers stop up on the windshield then go down to park .wipers don't park when shut off. i don't have any info on saturns . i can use any help . also i have a code u1b01 and c171b with a skip at idle.thanks	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	2000 Buick Regal LS 3.8L Engine VIN: 2G4WB52K5Y Thanks again guy's I am sure the problem will be resovled as soon as my customer slows down enough to let me fix it.The majority of the replies point to the the steering column ignition switch area. thanks again to all.	18
	2002 Buick Century Custom 3.1L oil fill cap VIN: 2G4WS52J32 I received many replies from intake manifold gaskets to give it a hard run down the highway. I don't think it is intake gaskets as the car has lost no coolant, I talked to the original owner last night. I also beleive this because of the moisture being clear a...	19
	1968 Chevrolet camaro 327CID ring and pinion I WANT TO START WITH A SINCERE THANK YOU TO THE 43 RESPONSES TO THIS REPAIR.a TOSS UP BETWEEN COMPLICATED AND NOT COMPLICATED WERE THE RESPONSES.AFTER COMPLETING THIS REPAIR I WOULD HAVE TO SAY USE COMMON SENSE.I ENDED UP USING THE .027 SHIM UNDER THE PINION,W...	44
	1993 Chevrolet S10 Blazer Tahoe 4.3L Differential VIN: 1GNDT13W0P Thanks to all that replied, I checked the cable that goes from the vacuum actuator to the front diff. and it was sticking. put a new cable on and all is good! Thanks again for the great advice.	11
	1993 Chevrolet S10 Blazer 4.3L No Start, Surge, Stall VIN: 1GHDT13W4P i recieved so many replies. the final fix was a fuel pump. it had good pressure but volumn was questionable. new pump had less pressure and the same volumn but it works perfect. we drove around with a gauge strapped to the w/s and we never saw a problem but it...	31
	1993 Chevrolet S10 Blazer Tahoe 4.3L bogs warm VIN: 1GNDT13W1P Well, I'm going to close this one even though I don't know what the problem actually was. The customer finally told me that he's had a rich running problem for about a year that he had just resolved by replacing the pressure regulator. Most responses agreed wi...	28
	1995 Chevrolet K3500 5.7L abs light VIN: 1GBHK34K0S hey guys, well i learned real quick that 3mph is the default value for abs( to keep from engaging at lower speeds?)the lf speed sensor was bad but the bad module was reporting the same speed on that wheel as the others. also all the codes went away after repla...	7
	1996 Chevrolet Monte Carlo Z34 3.4L Hesitation, Surge, Cuts out, Misfire VIN: 2G1WX12XOT Thanks to all who took time to reply. I replaced the PCM with a junk yard part. The lock-up point raised to about 38 mph from 25 mph. Customer is happy. Thanks again Craig	5
	1998 Chevrolet Corvette 5.7L traction control VIN: 1G1YY22G4W i am trying a new pcm. my mastertech tells me i need cable j-42236-a to flash the new pcm. i am trying to locate the cable. as soon as i find it,i will update.	4
	2000 Chevrolet Silverado 1500 4.3L No Start VIN: 1GCEC14W7Y well the plot thickened on this one somewhat. I had some missinformation, this last time the pump failed my tech doing his normal diag process found that this time when he moved the harness at the pump the pump came to life. So he replaced the harness connecto...	15
	2000 GMC C6500 7.4L aux light on VIN: 1GDG6H1B1Y tim was very big help,he is very knowledgeable in these brake systems and a very good resource. thank very much to all that responded.it turn out be a relay on the firewall was defective,that operates the aux motor on the hydro boost unit	6
	2001 Oldsmobile Silhouette Premiere 3.4L security light VIN: 1GHDX13EX1 After replacing the vehicle theft module and reprogramming the new keys all works ok. On this vehicle you have to program both keys seprate.	3
	2001 Oldsmobile Alero GL 2.4L Misfire, MIL Lamp on thanks to all that helped.coil housing was 10 mounths old, installed off shelf new one no change. r&r pcm reflashed it relearned pass system, no change. ordered new coil housing from other parts vender r&r it car fixed!!! defective part costed me time witch is... Trouble codes: P0300 (random missfire).	4
	1995 Pontiac Bonneville SE 3.8L no start VIN: 1G2HX52K4S well thanks too all that replied you all gave great info. At the end i pupped in a known good computer and inspected all wiring but still had no comunication with scanner. replaced fuel pressure regulator because pressure was a little on the high side. install...	23
	1999 Saturn SL2 1.9L dash VIN: 1G8ZKS270X Fixed and down the ROAD. Thanks the all that took the time to reply. As many of you stated there was a TSB about opening the drain, as soon as we opened them up the river began to flow.The local dealer had no idea how to repair...once again iATN proves it's wo...	6

(Also Available: All, Asian, Chrysler, European, Ford, GM.)