GM Automotive Technicians Technical Discussion and Fixes for Sep 8, 2005

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Open Help Requests for GM

	Help Request	Answers
	1994 Buick LeSabre Custom 3.8L Poor Idle Quality VIN: 1GEL6259XC members,the shop has a 94 buick la sabre that another tech is working on has a obd2 dlc,but as we all know thats not rite, should be old style gm connector.tryed 3 different scanners no comunication. from what i seen and heard car is running rich,idles poorly ...	View
	1992 Cadillac DeVille 4.9L digital lights on dash, fuel, and havac VIN: G6CD53B9N4 thanks for any help fellow techs. I have tested all powers and grounds to bcm. have unplugged all components with vacuumm fluresent lighting. Can not get 16v power out of bcm for these items. Get a blip of power when key cycled. Wiring diagrams show that bcm s...	View
	1992 Cadillac Seville 4.9L air cond cooling VIN: 1G6KS53B7N customer states a/c works fine for 5-10 minutes which it does and a/c display has temp read out which is accurate, then after 5 miniutes, a/c display shows only dashes where temp display was and only hot air comes out of the of defrost outlets, try to change t...	View
	1997 Cadillac DeVille 4.6L hard start VIN: 1G6KD54Y6V I have this car in here that is hard starting after sitting for a period of 4 hours or more or overnight. It will start every time but it will crank for too long of a time before it starts. When this vehicle first came in, I could not get the vehicle to act up...	View
	1998 Cadillac Seville SLS 4.6L Head Gaskets VIN: 1G6KS54Y8W I had this Northstar come in for overheating at high RPM. The only visible leak I found was the water pump/thermostat crossover from those crappy plastic gaskets(does anyone make a better version of those?). I pulled the water crossover and replaced the gasket...	View
	1985 Chevrolet Camaro Berlinetta 5.0L Excessive Emissions, Poor Idle Quality, Surge, Cuts out, Stall, Misfire, Poor Fuel Economy VIN: 1G1FP87E9F hello andd thanks for any help in advance im the third person to work on this car i have found the system that the problems on...and im thinking a ground problem..this car will run as long as the altinator is disconnected...as sooon as you plug the alternator...	View
	1987 Chevrolet R10 Custom Deluxe 4.3L Hesitation, Cuts out VIN: 1GCDR14ZOH ok, this truck will start and idle fine. when you drop in drive or reverse it sometimes will run, other times it will quit. if you pump the gas it will clear up and run fine. driving down the road, it will drive fine for about a mile, then start hesitating. wi...	View
	1992 Chevrolet Corvette 5.7L No Start, Poor Idle Quality, Hesitation, Cuts out, MIL Lamp on VIN: 1G1YY23P6N looking for a better way to test for possible bad ccm. or has anyone run into a ccm code 41 serial data malfunction Trouble codes: 51 (memcal or pcm failure), 41 (ccm code for pcm serial data malfunction)	View
	1994 Chevrolet Corvette 5.7L Starting VIN: 1G1YY32PXR We have a car that we have not seen act up so I dont have a lot of test data to pass on. The customer states that the car will not start sometimes. They say that it is not a hard click (like the starter) when it acts up(for what that is worth.)I have checked t...	View
	1994 Chevrolet S10 Blazer 4.3L Fuel pump VIN: 1GNTD13W6R Greeting Fellow Techs, Small problem here, maybe someone has seen it before. Sometimes when you turn the engine off the fuel pump continues running, and if left unattended will run the car battery down. I checked to see of the ECM is powering up the relay duri...	View
	1995 Chevrolet K1500 5.7L brake pedal VIN: 2GCEK19K3S Brake pedal is always hard. Booster line has 20 in vacuum at all times. Booster holds vacuum with no leak down. I find no adjustment for brake pedal rod between pedal and booster. Is there some other place to adjust rod travel? Vehicle will stop well if pedal ...	View
	1997 Chevrolet Corvette 5.7L Cuts out VIN: 1G1YY22GXV I have searched Mitchel on demand and cannot find much info for this problem. The car starts and runs fine until the car starts rolling. As soon as a wheel speed sensor signal is produced the engine shuts down. I am stumped! Any help would be appreciated. I am... Trouble codes: P1571	View
	1999 Chevrolet S10 2.2L Hesitation, Low Power VIN: 1GCCS1443X This is a vehicle that was passed down from another tech. It is very sluggish and feels almost as if it lacks fuel or has a plugged exhuast. Both of which I have checked. I have checked compression, all cylinders have 165 psi. I have diconnected exhaust and dr...	View
	1999 Chevrolet Tracker 2.0L Compressor VIN: 2CNBJ13C2X Hoping someone out there can figure out what Im missing here. This Tracker came in with the compressor locked up. Unbelievable what these things cost, over 900.00 and I could only get one from the dealer. At that expense I was scared not to replace everything....	View
	2000 Chevrolet Monte Carlo LS 3.4L engine VIN: 2G1WW12EXY This vehicle was towed into shop with a overhead problem. Mechanic replaced head gaskets and intake. On this engine the intake and exhaust push rods are of different length and of course he reversed them on several holes and bent push rods and damaged valves o...	View
	2002 Chevrolet Trailblazer LS 4.2L converter clutch VIN: 1GNDT13SX2 was worked on by another tech who did not find a problem and replaced v/b and torque converter. came back right away and i got it. did not have any tcc at all in any gear when commanded. function tested solenoids with the j whatever alum block while still cone...	View
	2004 Chevrolet Silverado 1500 5.3L Stall VIN: 2GCEK19V52 hello techs this trk came in for a trany service and asked about a intermittant trouble. we ran a scan and came up with a u0107 code. when trk acts up it has low power or poor accleration and the message center has a low power message across the screan. our d... Trouble codes: U0107	View
	1991 Geo Prizm 1.6L MIL Lamp on VIN: 1Y1SL3450M Hello , I really have a problem with this GEO. I have posted a help request for this car before but I really did not get any response that did not help me. My customer has been so patient with me I really would like to help him out by repairing this car. The c... Trouble codes: 21 (02 sensor short or open circuit)	View
	1997 GMC Jimmy SL 4.3L Blower motor VIN: 1GKDT13W0V This Jimmy came in with a blower motor inop. in all speeds. I was just wondering if there are any flat rate tricks to r&r the motor since it looks like it is stuffed in there and not easy to get at. We don't have much in the way of repair manuals on this model...	View
	1999 GMC Jimmy SL 4.3L abs VIN: 1GKDT13W9X This Jimmy came into our shop with a complaint of a clunk sound comming from front during a low speed stop. We road tested the car and experienced the symptom. My scanner shows no codes. One month prior it had an ABS light on and we found a dead left front sen...	View
	1994 Oldsmobile 88 Royale 3.8L Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire VIN: 1G3HN52L2R car runs fine but when hot idles poor and put in gear dies also fuel filter gets very hot	View
	1997 Oldsmobile Cutlass Supreme SL 3.1L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1G3WH52M4V This GM is driving me crazy.Car came in with misfire about six weeks ago. Replaced number 3and number 2 injectors leaking. We replaced with napa injectors. Came back week later both leaking again. Again replaced with napa. Back in three days later leaking. Che... Trouble codes: P0300	View
	2000 Oldsmobile Bravada 4.3L Misfire VIN: 1GHDT13W4Y Vehicle came in with a intermittent misfire under loead and when cruising. Tuned it up and cleaned injectors. Added cleaner to the tank and returned to customer. Came back one week later, never having improved. We test drove with the scanner hooked up and watc...	View
	2000 Other GM Goshen Coach 6.5L compressor VIN: 5B4LP37F6Y The bus came in to get the front a/c system filled. This bus has two seperate systems. I filled with r-134 and it is ok at idle. High pre. 250, low pres. about 40 cold air out vents ambient air 85F. When you speed the engine up the compressor starts cycling on...	View
	1985 Pontiac Firebird 2.8L Excessive Emissions, Poor Idle Quality VIN: 1G2FS87S2F it seems these old gm's are the worst for me, i have been on this car almost all day and not much closer. i need some help hard to start, will not idle. if you floor this car it will start and rev up just fine sounded to me like way to rich. scanned and got t... Trouble codes: 34 (maf sensor or circuit too low)	View
	1997 Pontiac Firebird Formula 5.7L Radio, windows VIN: 2G2FV22P3V Radio and power windows quit intermitantly. Have replaced ignition switch to repait. Car came back a few days later. We had trouble getting the problem to show itself. Finally found that it most likely will happen when turning key on without starting engine. R...	View
	2000 Pontiac Grand Am SE 2.4L Daytime running lights VIN: 1G2NF52T8Y Please help, this car came in with the customer complaining of no ac and that the lights came on in the middle of the nite and couldnt be shut off. The ac is fixed but im pulling my hair out trying to figure out the lights. The body computer had a B2602 code(D...	View
	1999 Saturn SL2 1.9L dies, inside fuse block problem?? VIN: 1G8ZK5276X customer stated that car stalls while driving, radio inop., door locks inop.---he wiggled inside fuse block and removed and re-installed ignition 1 fuse, car started and radio and locks all work ok--- has happened 2 times now-- everything is working fine now t...	View
	2000 Saturn LW2 3.0L MIL Lamp on VIN: 1G8JW82R4Y vehicle came in with mil light on code p0102 perform pin point test with scanner hooked up and monitoring mass air flow the voltage stays at a fixed 1v tested circut 416 4.9 volts jumpered 416 to 492 no voltage change still 1v on scanner. looked for ecm to tes... Trouble codes: P0102	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	1994 Cadillac DeVille 4.9L Cuts out, Stall, Misfire VIN: 1G6KD52B4R well thanks to some backyard (&^$^#()* mechanic who replaced the starter and didnt put the power lug bolt tight is why this had its problem thanks to all replies they where all good ideas but the one that help the most was the ground TSB because i looked at th...	8
	1990 Chevrolet Celebrity 3.1L No Start VIN: 2G1AW84T8L Thanks to all who replied. Most of you lean towards bad ecm. Since I don't get scan data as well as no flashing mil light when grounding at aldl, I decided to replace ecm ( ac/delco ) and all is well now. I can read scan data and test drove with no other compl...	24
	1992 Chevrolet Camaro Z28 5.0L fuel smell VIN: 1G1FP23F4N Well, car has been gone for a few weeks and I be grinning that I had no phone call that informed me that the smell is still there or has returned, my conclusion to the problem was a few things, If you note the mileage on the vehicle, it was low for the year 38...	8
	1993 Chevrolet Camaro Indianapolis 500 Pace Car 5.7L module faults VIN: 2G1FP22P1P Thanks to all who replied. Bill was right 93 does not have an oil temp sender.One of the reasons I posted the request was because I do not have access to the QDM charts and wanted to know what they controlled. Thanks to Jimmy for responding quickly and pointin...	5
	1994 Chevrolet K1500 5.7L 4 lo switch VIN: 2GTEK19K1R This vehicle is finally working properly. After checking all grounds and 4 lo switch. I checked the test connector for the buffer next to throttle body. With that connector unplugged, trans worked perfect. Customer was satisfied with that. Not wanting to spend...	3
	1996 Chevrolet K1500 Cheyenne 6.5L No Start, MIL Lamp on, no throttle response VIN: 1GCEK19S3T Well I am very thankful for the replies. Which included, a buletin about having the tank over half full because of the pickup tube cracking, checking for bubbles in the return line, IP module, cam sensor. I have talked with the customer and am sending him to a... Trouble codes: P0251, P0370, P0606, P0406.	5
	1996 Chevrolet Express 1500 5.7L fuel gauge VIN: 1GBFG15R8T Most of the replies I recieved were about the grounding of the fuel pump and sending unit system. Many also comented that I should have only used a factory original part and not the aftermarket one we used. There is a big differance between the aftermarket par...	10
	1997 Chevrolet Blazer 4.3L No Start VIN: 1GNCS13W5V this vehicle had a bad set of injector replace injector and the vehicle is running.	32
	2001 Chevrolet Monte Carlo SS 3.8L air bag system VIN: 2G1WX15K01 First off I would like to thank Stephen,Bern,Cory,John and Karl.All the info. was very helpful, I appreciate your time on this. What we have found on this car is apparently the side air bag located in the seat was the culprit. Or at least the wiring for it, we...	5
	2001 Chevrolet S10 4.3L Poor Idle Quality, Stall VIN: 1GCCS19W31 We fixed it! Thanks to “Ricky from Florida”; “Nick from New Hampshire”; “James from New York”; “Richard from Washington”; and “Bruce from Georgia”, I was able to figure out what tests I should do next. Most of your responses suggested testing each wire to ... Trouble codes: P0506 (Low Engine Idle).	5
	2002 Chevrolet Malibu 3.1L MIL Lamp on VIN: 1G1ND52J72 Thanks for all the replies. Almost all said use a factory converter. Ordered one and installed it yesterday. So far so good. Thanks for all 20 replies.	22
	2002 Chevrolet Trailblazer LS 4.2L Front Differential VIN: 1GNDT13SX2 I guess not many techs has had the previlage to work on one of these jewels. We found that the selector assembly on the right side of the pan was the problem. The grease inside this unit was hard and restricting the fork from moving the sliding ring to total e...	5
	1995 GMC Jimmy SL 4.3L Vacuum Actuators VIN: 1GKDT13WXS Well thanks to the 14 posts returned we sifted thru and got the answer. Many of you wrote about checking the vacuum line at a vacuum switch on the transfer case. sure enough the switch was leaking oil internally and sending transfer case oil into the lines. Th...	13
	1999 GMC Jimmy SL 4.3L 4 low VIN: 1GKDT13W0X The transfer case module was located in the passenger kickpanel -and there was corrosion on plug causing the problem as most of the replies suggested.The wire that signals the VCM for low range was shorting to the case through all the corrosion -The TCCM costs...	6
	1994 Pontiac Bonneville SE 3.8L Cuts out, MIL Lamp on VIN: 1G2HX52L4R I recieved many replies about problems with ecms in those years so I decided to change it and all is well. Trouble codes: P0341, P0342.	20
	2000 Pontiac Grand Am SE 2.4L ABS module VIN: 1G2NF52T3Y I am sorry to have to report that this customer chose to decline any more testing on her vehicle. However, I did receive five replies that did contain some useful information. It appears that we may have two separate issues. Two of the replies suggested that t...	5
	2002 Pontiac Grand Prix SE 3.1L Hesitation, Poor Fuel Economy, NO POWER VIN: 1G2WK52J92 the cat was our problem,baro sensor still reads 14 psi,i'm not sure why,we used both genesis and tech 2, both read same,car runs great and fuel trims are good,we believe the baro reading to be a software problem. thank you for all your great tips/help,blas (mi...	10

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