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Open Help Requests for GM
Help Request Answers
1982 Cadillac DeVille 4.1L long block
My customer just inherited this pristine Cadi from his father. The engine has a pronounced rod knock. Given the history of these engines, I won't install a used one (even if I could find one) and rebuilts are non-existant. Anyone ever converted one of these to...		 View
2001 Cadillac Catera 3.0L radio,fuel door,trunk
Customer came in today stating that, his wife was driving there car today and it just shut off on her. The car started back up and they continued driving. A little later they noticed that the radio wasn't working along with the fuel door and the electronic tru...		 View
1966 Chevrolet impala 350CID linkage?
Hello fellow techs, I have a powerglide trans that come in for a leakage problem, seemed it leaked a rather large puddle if allowed to sit for long periods of time, of course it would not really leak for us, it was, you guessed it, intermittent. We suggested a...		 View
2002 Chevrolet TrailBlazer 4.2L Starting
Hey everyone. Thank you ahead of time for any input and advice! The customer just bought the vehicle. It currently has a single key not a huge set of keys. It has a current B2691 key in ignition ckt fault. I got it to start once. Most of the time it wont even ...		 View
2002 Chevrolet Express 5.7L oil pressure
Van starts fine. After runing/idling short period of time, oil pressure drops to 0-5 pounds. There is a lifter noise. Raising the idle causes the noise to go away, but pressure will drop when low idle returns.		 View
2003 Chevrolet Silverado 4.3L compression
customer was driving down the road and came to an abrupt stop. vehicle died , and would not restart. cranks , but sound like the motor is binding or klunk noise is heard. then see related repairs above. we then towed the vehicle into the service facility. c...		 View
2004 Chevrolet Silverado 6.6L Hesitation, Cuts out, Misfire
Test drove vehicle, under hard accel in 3rd and 4th gear, vehicle bucks rather violently. Feels like either an ignition miss, or tranny slip, but pretty violent. In 4th gear, it hits 60mph at 3200 rpm and feels like it hits the rev limiter, cuts out as you giv...		 View
2006 Chevrolet Uplander 3.5L No Start
this vehilce will crank and crank and not start unless you push on the gas pedal. once started it will run fine. no trouble codes. fuel pressure o.k. tech 2 scanner shows all drive by wire sensors working and agree. has spark when cranking. tried maf, no fix. ...		 View
1998 GMC Suburban 5.7L No Start, Poor Idle Quality, Surge, Misfire, MIL Lamp on
After we had completed the job and went to start the vehicle it would not start it just back fires and will not idle. We found that the timing chain had excessive amount of movement we installed new timing chain, sprockets, cover and crank position sensor. Sti...		 View
2000 GMC Jimmy 4.3L transfer cas
Vehicle came in with complaint of intermitent service 4WD light on/flashing scan tranfercase computer had code C0362, diagnostic tree-disconnect tranfer case shift module and connect test light between ground and 4 low indicator signal, no light check harness ...		 View
2000 GMC Jimmy 4.3L 4x4 light on
vehicle has 236 transfer case with auto and 2, 4hi,and 4low buttons. when you start the vehicle and you here a click from 4x4 module in left kickpanel, the 2wd light will come on and all 4x4 operations will work. once in a while you won't here a click and that...		 View
2002 GMC Yukon 6.0L Excessive Emissions, Poor Idle Quality, Hesitation, Misfire, MIL Lamp on
This Denali arrived in our shop after customer drove through a large puddle on a city street during a rainstorm. Engine gulped enough water to bend 1+ rods. Vehicle was not submerged, and actually ran long enough to get half a block down the street before dyin... Trouble codes: P0300 (Random misfire).		 View
2003 GMC Sierra 6.6L Excessive Emissions, blue/ white smoke
do not know too much about the truck but here is the history from the customer this truck came used from california when customer got unit 3 months later it started smoking at idle bluish white stinks of raw fuel no codes . Thgermostas were changed from 180 's...		 View
1998 Oldsmobile Achieva 3.1L all system
we have a 98 olds achieva here, battery light on and no current out of alt. made sure of power wire from batt to alt, good, has signal voltage from ecu, and good ground. we replaced alt and battery. problem seemed to be fixed. customer left here and 30 minutes...		 View
2001 Pontiac Grand Am 2.4L engine vibration
This car came in for a vibration , only at idle . Vibrates hard, but raise the idle a little and it smooths out. We seen the water pump leaking , so we thought maybe the water pump was it , well we replaced the pump, but the same thing. No codes, no misfire, ....		 View
2007 Pontiac G6 3.5L MIL Lamp on
Hi Guys and Gals, I'm just looking to see what kind of signal this mass air flow sensor should make. This is a crash car (no warranty) and had wiring repaired which I have triple checked. My problem is I only have a approx 13v flatline signal while car is runn... Trouble codes: P0102 (low or no mass air flow signal).		 View

Fixes & Summaries for GM
Fix/Summary Answers
2002 Buick Century 3.1L Misfire, MIL Lamp on
Thanks for the replies, unfortunately, none of them got to the problem. After staring at the misfire graph on my Tech2, showing a major misfire on #3 cylinder only, I decided to think outside the box. I checked different cylinders for issues with spark and fou... Trouble codes: P0300.		 15
1997 Cadillac DeVille 4.6L LR speed sensor reading incorrect
I do hate to say it but there is no fix on this car. The customer has decided to take the car to the dealer. I am really sorry and I thank you for all the replies. I did check with napa-identifix and they said the same thing that I did and that was the problem...		 6
1998 Cadillac DeVille 4.6L Radio, power windows
Thanks to everyone for the info. Customer picked up car before we could determine what was going on. He brought it back a few weeks later and everything was working as should be. We had it in the shop all day and repeatedly turned the key on and off and then o...		 6
2004 Chevrolet Aveo 1.6L MIL Lamp on
AFTER FOLLING TSB #05-06-01-030D, INSTALLING A NEW CRANK SENSOR JUST TO BE SURE. I HAD THE CRANK RELEARN RAN BUT IT TOOK 3 TRYS TO GET IT TO STAY. I HAVE DROVE IT 5 DAYS WITH NO OTHER PROBLEMS, SO I AM RETURNING IT TO THE CUSTOMER. THANKS FOR ALL YOUR HELP. Trouble codes: PO300 (intermitten misfire), PO700 (tcm set code thru pcm), PO700PD (na), PO1781 (tcm comm to bcm about engine speed malfunction).		 11
2004 Chevrolet TrailBlazer 4.2L MIL Lamp on
thanks to all who replied, 10 out of 13 said it was the thermostat, which fixed this vehicle. although it did not have a running hot problem, i guess the computer is so sensative to temp that any fluctuation will set the code. car has been gone for a week and... Trouble codes: p0128 (ect coolant temp sensor).		 13
2006 Chevrolet Uplander 3.9L Accessories
Vehicle returned yesterday; thanks for response's. White wire at bcm worked ok. I asked another tech about using that wire before I posted and was advised that it shouldn't be done due to some sort of residual voltage?!!! Thanks again for the quick help!		 3
1989 Pontiac 6000 2.8L No Start
Well thanks again for all the help it is indeed the injectors customer had 4 of the 6 go bad causing the problem but customer doesnt want the new injectors put in because of the cost and cant locate any used for them and they havent decided what to do with the...		 22
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