GM Automotive Technicians Technical Discussion and Fixes for Jul 28, 2009

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Open Help Requests for GM

	Help Request	Answers
	1991 Buick Skylark 2.5L Stall VIN: 1G4NV54U6M HELP GM TECHS!!This one is eating me alive. Runs great and accellerates all day long. When coming to a stop it stalls. When it first came in we verified the complaint several times. When we got the chance to hook up the pressure guage it had 11psi and then ama...	View
	1996 Buick Riviera 3.8L column VIN: 1G4GD2218T Thanks in advance. The column on this car could be moved up and down some. Disassembled the column thinking I was going to tighten the tilt bolts, but as I was taking it appart I found one of the pivot pins that the tilt part pivots on laying in the trim under...	View
	2002 Buick Rendezvous CX 3.4L electric windows,gauges,door locks VIN: 3G5DA03E12 This vehicle will not start,the power windows and door locks do not work.The security light and service engine soon light is on,and the traction control and abs lights are on.The DRL wont work,and the interior lights do not come on.	View
	2006 Buick Rainier CXL 4.2L rear speed signal VIN: 5GADT13S96 Hello, Customer complaint Right Rear brake grabs. Did rear brake inspection (disc with drum parking brake). Looked ok slight axle seal leak. (don’t think a parking brake can grab from the leak) 1.Put on Scanner NO SPEED SIGNAL FROM RR REAR sensor. 2. Only hist...	View
	1997 Cadillac Eldorado 4.6L detonation VIN: 1G6EL12Y7V Thanks in advance for all that are willing to help on this one. When this car is hot the engine pings under slight acceleration. You can power through it if you mash it to the floor. Fuel pressure is within specs. I have no codes. I can check the egr operation...	View
	2000 Cadillac Catera 3.0L MIL Lamp on VIN: W06VR54R1Y Unable to program the ecm. I replaced the ecm because of code p1280. The app sensor 2 was stucj on 2.50 volts. I replaced the ecm and now the app 2 is reading correctly. I cannot program the ecm. I have never programmed a catera. I know it is a german built ca... Trouble codes: P1280	View
	2009 Cadillac Escalade 6.2L Starting VIN: 1GYFC26229 I have this 09 Escalade, 2008 Suburban and 2007 Tahoe with the same intermittent "no crank" problem. Engine will NOT spin over according to customers. 2 customers said the problem acts like a dead battery, we get the vehicle here and it starts. We installed ne...	View
	1985 Chevrolet Corvette 5.7L No Start VIN: 1G1YY0782F The vehicle came in as a no start with no injector pulse. If you spray starting fluid in the air horn the car starts and runs all day with good injector pulse. Original computer's processor was fried. Found knock sensor was shorted to power on the hot lead at ...	View
	1989 Chevrolet Corvette 5.7L Poor Idle Quality, LONG CRANK VIN: 1G1YY218XK I purchased this vehicle about 9 months ago. Right after purchasing the vehicle I brought it in for an oil leak. We replaced the lower intake gasket, we also went ahead and replaced the radiator hoses, bypass hoses, thermostat, spark plugs, spark plug wires, a...	View
	1995 Chevrolet Blazer 4.3L compressor VIN: 1GNCS13W6S hope you can help ,thanks in advance. well we replaced the oe unit because of noise that over got progressivly worst over time.replaced with new unit from DELPHI, flushed system ,replaced orifice tube ,and dryer ,everthing worked out well until couple months l...	View
	1998 Chevrolet Cavalier Z24 2.4L No Start, Stall VIN: 4G1JF32T8W owner says will stall when driving but will start after waiting awhile.sounds like ign. mod. I had this car for 2 weeks a month ago and never witnessed a stall. Owners said she's not driving it until the stalling is fixed.Well needless to say I've had it for a... Trouble codes: P0342, P0335, P0507	View
	1997 Chevrolet C1500 Cheyenne 5.7L brake lights VIN: 1GCEC19R0V brake lights work when jumped at switch connector,replaced brake ligt switch,lights still inop.found that switch is not closing when applying brakes.if i push on brake light switch with finger switch closes and lights work.No parts are missing according to par...	View
	2000 Chevrolet Silverado 1500 4.8L 2 - 3 shift VIN: 1GCEK19EV5 I installed a rebuilt GM trans into this 99 chevy, after I was done and test drove it the check engine light would come on for po758, then the trans goes into limp mode and stay in 3rd gear, unless I clear it. I believe this truck had this same problem before ...	View
	2002 Chevrolet Malibu 3.1L Excessive Emissions, Poor Idle Quality, Cuts out, Stall VIN: 1G1ND52J33 Thanks in advance guys. Ive got this malibu in here that is throwing me for a loop. This car will die at random then run rough pop back thru the intake and die,Ive noticed on the scan tool the timing going from 12-32 deg. of timing @ idle and bounces around, I...	View
	2002 Chevrolet Tracker ZR2 2.5L alternator VIN: 2CNBJ73412 Hello fellow techs, This tracker brought in by new recent owners with 1 month history of returning to used car dealer for charging system and stalling problems. Alternator was stinking and fried looking, regulator would sometimes allow nearly 18 volts and elec...	View
	2003 Chevrolet Express 3500 6.0L Misfire, MIL Lamp on VIN: 1GBJG31413 Hi Chevy Guys got this G3500 it has a big heavy box on it and im sure its overweight. it throws PO171 & PO174 both banks lean and it misfires alot. it has new mass air sensor plugs wires exhaust manifolds and we put 2 front o2s on it 3 weeks ago... and the bac...	View
	1997 Geo Tracker LSi 1.6L Hesitation, Surge VIN: 2CBNBJ136X This is my vehicle. It has really gotten doggy. Also it surges when driving at first startup. I watched the gpm from the MAF and doesnt look right but then what looks right any more. I backed off the exhaust from the maniflod and still no difference. Another o...	View
	1994 GMC K1500 Sierra SL 5.7L Surge, Stall VIN: 2GTEK19K1R This vehicle is stalling when put into gear. I pulled the engine from a 1995 Tahoe and installed the engine into this 1995 GMC Pickup. The engine will idle, but stalls when put into gear. The engine surges as if it was missing and then stalls. I have repaced t...	View
	1997 GMC Savana 2500 4.3L Excessive Emissions, Poor Idle Quality, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1GTFG25W3V at start up runs rich both 02s over 1 volt and misses on cyl 1,3,5 injector pulse 3.o bank 1, 5.0 bank 2 engine light will then come on and go to open loop and smooth out checked ignition ok any help please	View
	2005 GMC Envoy XL SLE 4.2L Poor Fuel Economy VIN: 1GKET16S45 have a envoy with mileage complaint runs about 12-14mpg no other driveability issues is this normal no warrenty left --burned 3/4 tank for [...]?? just doing research before cust comes in ...thank you in advance	View
	1991 Pontiac Grand Prix SE 3.1L No Start VIN: 1G2WJ14T2M Orginally this vehicle had a history of not starting after running for a while, being shut off This the first emc waqs replace when the car would stall after a short idle time warm. Now it's progressed to running for a short time ( 5 to 15 minutes ) then shuti...	View
	1996 Pontiac Firebird Formula 5.7L Poor Idle Quality, Hesitation VIN: 2G2FV32P9T car came in about a month ago. had intermittant hesitation when trying to kick it down while cruising. had disconnected egr at that time since everything else looked ok and ran fine. replaced egr valve and solenoid with gm parts and tested. seemed to run fine ... Trouble codes: P1810, P1870	View
	2001 Pontiac Bonneville SE 3.8L Stall VIN: 1G2H54K014 I have a 2001 bonneville that has a intermittent stalling problem that is getting worse. Customer first said car would stall at stop lights and going around corners. We cleaned tholle body and check fuel pressure 60psi every thing else looked good. Car was pic...	View
	2001 Pontiac Montana 3.4L ac VIN: 1GMDX03E21 Having trouble with this low mileage Montana. AC not cold enough. I suspect air mix problem and was hoping someone has run into this and can give me some tips. At first thought I had a freon issue (I am aware of condenser bulletin), this vehicle has a new cond...	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	1999 Buick Century Custom 3.1L security light VIN: 2G4WS52M2X this issue is very intermittent. has happened 3 times in the last 3 months. my plan of attack is to measure the resistance in the key and install a resister of equal value in the wiring and bypassing the poor design of the system. I did this to my taurus air b...	21
	2000 Chevrolet Monte Carlo SS 3.8L Hesitation, stumble @ 45+ VIN: 2G1WX12K4Y Kent was right. The rear block off plate is leaking smoke/oil and will have to be pulled and repaired at a later date thanks to all thet helped out.	4
	2000 Chevrolet Suburban 1500 LT 5.3L MIL Lamp on VIN: 3GNFK16T2Y it ended up being the pcm needed reflashed by dealer all is well thanks for all the replies Trouble codes: P0137.	7
	2001 Chevrolet Monte Carlo SS 3.8L No Start VIN: 2G1WX15K31 I believe this car is fixed. A couple guys brought it to my attention that fuel is only affected by the security not spark. I check the crank sensor and it was weak. It also fixed the P1811 maxium adapt long shift. I drove the car 200 miles with out any probl... Trouble codes: P1546 (A/C clutch control relay circuit), P1811 (Maxium adapt long shift), B2960 (Passlock cylinder Data incorrect), B2964 (Key-in ignition circuit high), B3031 (Security system controller in learn mode), B3128 (Driver door unlock output short to battery).	8
	2001 Chevrolet Monte Carlo SS 3.8L Surge VIN: 2G1WX15K31 Thanks for all of your help. Most everyone was right about the cat being plugged. I am taking the car to the Chevy dealer who said that this car's cat is covered for a period of 10 years. I will let everyone the outcome of the car and the warranty when I get t...	18
	2001 Chevrolet Prizm 1.8L MIL Lamp on VIN: 1Y1SK528X1 thanks to all that helped. the factory mass air flow sensor seems to have fixed the problem. I was realy scepticle about this fix but i replaced it with a factory one and the code has not returned. Trouble codes: P0171.	9
	2001 Chevrolet Express 3500 5.7L unwanted high idle VIN: 1GDJG331R5 Sorry about the delay in closing, but wanted to keep the bus on the road as long as possible as it was a "very" intermittent condition. We replaced the IAC valve with a GM part and van has had no trouble with high idle. I wish I could say that this is 100% the...	8
	2003 Chevrolet Silverado 2500 HD 6.6L No Start VIN: 1GCHK23143 Well as most everyone suggested it was the injectors.They were still covered under warranty,so it went to the local chevy dealer and got a full set.Customer said it hasn't ran this good the whole time he has had the truck.THANKS AGAIN.	7
	2004 Chevrolet Colorado LS 3.5L Stall, MIL Lamp on VIN: 1GCDT136X4 Thank you for your replies. After checking wiring at ecm, we came to the conclusion that the ecm was not acknowledging signal from crank sensor. Replaced ecm, fixed truck. Trouble codes: P0335.	2
	2004 GMC Yukon XL 1500 SLE 5.3L Pcm fuse 1 VIN: IGKFK16Z44 Thanks to all of the techs who replied. There were many different posts and some leading the wrong way. I removed the fuse panel in the engine compartment first and low and behold I found a small chipmonk and he was knawing on the wires that left the load side...	16
	2005 GMC C4500 Topkick C4E042 6.6L Low Power VIN: 1GDE4E3285 I must be too old. those silly buttons on the dash that only have icons. One of them is a PTO switch even though the vehicle has no PTO, I guese it has to be fitted with one due to it's potential useage. I switched off the PTO switch and our truck runs grea...	7
	1997 Oldsmobile Achieva S 2.4L Excessive Emissions, MIL Lamp on VIN: 1G3NL52T9V THANKS FOR THE HELP CONCERNING THE 1997 ACHIEVA 2.4 CODE PO171 LEAN BANK 1 SENSOR 1. OF THE 3 RESPONSES O2 CIRCUITS TESTED GOOD. NO VACUUM LEAKS WERE FOUND. WE DID FIND BAD GROUND CONNECTION AT THE TAN WIRE TO THE BELL HOUSING. WE REPAIRED THE CONNECTION, RETE... Trouble codes: P0171.	3

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