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International Automotive Technicians Network
Prev Professional Automotive Repair Technical Discussions for January 25, 2010
International Automotive Technicians' Network (iATN) - Members Only
(Also Available: All, Asian, Chrysler, European, Ford, GM.)
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Open Help Requests for GM
Help Request Answers
1993 Buick Century Custom 3.3L Starting VIN: 1BU1C12345
I have one here that is really stumping me. This Buick was towed in for a no start. Quick check had spark, weak! Fuel injector pulse. No codes. Installed new crank sensor, no help. Removed found plug gap at .090. Plugs, & wires had not been changed. Installed ...
2004 Buick Rendezvous CXL 3.6L No Start VIN: 3G5DB03704
Went on a service call for a dead battery. It had headlights but they were dim. Battery voltage was 9 volts. I put my jump pack on it and attempted to start it. No crank. I noted security light on and went back to get a scan tool. Found all kinds of communicat... Trouble codes: P1631
1998 Cadillac Seville STS 4.6L windows VIN: 1G6KY5490W
No power windows from any switch. Good communication from Tech 2. No codes. Can not get windows to work even from scan tool command. Scan tool does recognize window switch commands from all doors and master switch. I can get windows to operate with jump leads,...
1993 Chevrolet S10 4.3L No Start VIN: IGCCTI9ZXP
Truck towed in no crank problem customer came out of store went to crank nothing. got to shop tried key nothing jumped starter nothing replaced starter engine turns over good now no spark checked all fuses good. checked spark at coil no spark put coil of runni...
1994 Chevrolet Astro 4.3L Misfire VIN: 1GBDM19W3R
Vehicle came in with a no start condition.I replaced the ignition coil and got it to start.Has a misfire on cyl. 1 and 5.Checked fuel pressue and found that it would fall out imediatly.I goffed up not thinking that this was a return fuel system and replaced th...
1995 Chevrolet K2500 5.7L Poor Idle Quality, Surge, Stall VIN: 1GCGK24K35
Truck came in for surging, lack of power, not wanting to shift. Found PCM faulty, transmission shifts fine now. When truck warms up, at steady throttle, it surges badly. Fuel pump was very loud, pressure was slightly below spec. replaced fuel pump, filter, and...
1997 Chevrolet Blazer LS 4.3L extended crank VIN: 1GNDT13W0V
Okay gentlemen- this one had been in many times before, all for complaints of drivability problems. First time around it was hesitation on acceleration when cold. Problem was verified and solved by replacing intake manifold gasket, tune up, and EFI Cleanout. N...
1998 Chevrolet C1500 WT 4.3L Cuts out, Misfire, MIL Lamp on VIN: 1GCEC14W2W
I am going nuts this is my uncles truck it started a year ago, i check back psi on exhaust, fuel psi, tune all was ok it is very intermitent, somtimes you will be driveing normal and if you hit a big hill 3/4 the way up it will lose power, missfire like you wo... Trouble codes: P0300
2000 Chevrolet C3500 6.5L No Start VIN: 1GBKC34F6Y
The other day the driver took the truck to the car wash and it started to stumble like it ran out of fuel and then stalled. I came down to the truck and opened up the air bleeder at the fuel filter and I will be honest the grossness that came out wasnt funny. ... Trouble codes: 1216 (660 -), 660
2002 Chevrolet Cavalier LS 2.2L Fuel gauge VIN: 1G1JH52F42
Check wires - powers - grounds ect. back 3rd time same fault. No codes, rest of gauges ok. Looking to use different Fuel pump manufacturer?
2002 Chevrolet Impala 3.8L fluctuating duty cycle VIN: 2G1WH55K52
Hello, The customer complaint is that the tach jumps and car surges at highway speeds on light acceleration. The car does it right at the moment the tcc engages, then smooths out. With the scan tool you can watch the tcc duty cycle fluctuating at least 10%....
2002 Chevrolet Silverado 1500 HD LT 6.0L Exhaust manifold VIN: 1GCGK13UX2
Just wanted to see if anyone knows any magic tricks for extracting a broken exhaust manifold bolt on this 6.0L. It is of course the rear bolt on the LH bank (nearly impossible to get at), drilled 1/8" hole with 90 degree angle drill, unfortunately due to clear...
2003 Chevrolet Malibu 3.1L blower motor VIN: 1G1ND52J03
Hello iAtn. We have a 03 chevy malibu that has water migrating into the blower motor, and soaking the carpet on the passenger side. It's water, not coolant. Has happened the last 2 times it has rained. We pulled the plastic cowl trim at the right bottom of win...
2004 Chevrolet Silverado 2500 HD 6.6L MIL Lamp on VIN: 1GCHK24154
The customer brought us the truck due to the MIL being on. We cleared the code and gave the truck back. The light stayed off for a couple of days but then came back on. The same codes are present as the first time. We have checked and cleaned all grounds. My n... Trouble codes: P0700 (Trans control system fault), U1800 (lost communication with FICM), U2104 (CAN bus reset counter overrun), U2106 (Lost communication w/trans control system)
2005 Chevrolet Silverado 1500 LS 5.3L Upshifting VIN: IGCEC14T35
Hi Guys, I hope some of you can lead me in the right direction. This is my personal truck. I purchased this truck brand new. The truck was built in 2004 and bought by me in June 2005. The complaint is a delayed 1-2 upshift. On some mornings, no problem. When t...
2005 Chevrolet Silverado 2500 HD 6.0L No Start VIN: 1GCHK29U35
This truck was sold off of the lot and next day whould not start. Wont turn over, makes no clicks or anything.You can jump across the starter and make it start. Put an ignition switch in with no luck- After reading some old posts we cleaned the ground wires un...
2007 Chevrolet Uplander 3.9L heater VIN: 16BPV13187
enigne runs at 210 degrees at idle. heater blows cold. rev engine to 1500 rpms heaters blow hot. has front and rear heaters. both heaters blow cold at idle and hot off idle. had problem before changing thermostat
2002 GMC Savana 3500 5.7L Poor Idle Quality, Hesitation, Misfire, MIL Lamp on VIN: 1GTHG35R32
Truck came in with a code P0300. Wet down ignition wires and found that the wires were arching. Replaced the ignition coil , wires, cap, rotor and plugs. Problem code P0300 still excists. Performed cylinder leak down test on effected cylinders ( cyl. 7&4), tes... Trouble codes: P0300 (multiple cylinder misfire)
2004 GMC Sierra 3500 6.6L Poor Idle Quality VIN: 1GTHK33254
We are at a loss on this, have spent hours tracing wiring. Suspect the FICM, but is a pricey part to replace being unsure. Has anyone run across this before, or know a way to test the FICM? The truck runs fine for 10 mins or so, then check engine light comes o... Trouble codes: P0208, P2149
1999 Pontiac Firebird Formula 5.7L Excessive Emissions, Poor Fuel Economy VIN: 2G2FV22G0X
I got a good one here for all the GM gurus. This bird will not go into closed loop. Whether at idle, cruise or anywhere in between. O2s show rich at idle and 2500 RPM, they hover about 800mv front and back both banks. Coolant temperature reaches 192F max at id... Trouble codes: P1637 (Generator L Terminal circuit)
2004 Pontiac Montana 3.4L radio, bcm, VIN: 1GMDX03E84
After replacing IPC (purchased from gm and preprogramed with vin and mileage) vehicle radio is Locked ..I unlocked the radio with tech 2 scan tool but the radio will not shut off when turning engine off ...removing ign key and then opening the door. It is supp...

Fixes & Summaries for GM
Fix/Summary Answers
2003 Cadillac Seville SLS 4.6L replace pads lamp on VIN: 1G6KS54Y23
Another fixed car goes down the road. Thanks IATN. Steve was correct; The reprogram corrects the "replace pads" light" (as well as the needed vehicle specific burn) Juan was right about same module and different car options. I installed a used module. It fixe...
1995 Chevrolet Blazer 4.3L Hesitation, Surge, Cuts out VIN: 1GNDT13W5S
THanx for all the replies they were all good. got veh to not start one morning it had spark and good fuel pr. yanked on inj wires and it fired up.. So I replaced inj harness with a new one from the dealer its been running perfect since.. Again thanx for the he...
2001 Chevrolet Malibu 3.1L instrument cluster VIN: 1G1ND52J51
It looks like the problem was water intrusion which ruined the BCM apparantly they think that if the windshield seal was leaking it could have caused this problem thanks guys!
2002 Chevrolet Venture LS 3.4L windows VIN: 1GNDX03E32
Thanks for all the replies. Turns out the recirculate door not operating due to the stepper motor not operating. Replaced the stepper motor and all is well now. Thanks again for all the replies.
2004 Chevrolet Malibu LS 3.5L MIL Lamp on VIN: 1G1ND52F64
this vehicle was a simple fix but as it was a used car dealer i didnt want to get to involved in it (you know those used car dealers, fix it as cheap as possible)as the dealer wanted me to just scan codes. jesse from missouri nailed it with a bcm code for dayt...
2006 Chevrolet Equinox LS 3.4L charging system VIN: 2CNDL13F56
Hello to all - this vehicle is fixed! Thank you so much for all the great replies. The fix turned out to be as unique as the problem itself. We traced the problem to the pcm, but when the module was disconnected it made no difference to the draw, we then fo...
2006 Chevrolet Cobalt LS 2.2L MIL Lamp on VIN: 1G1AK15F56
I may be jumping the gun here stating that I fixed this vehicle, the problem was intermittant and the customer has not brought it back since it's last visit. I did not have a chance to do anything to the vehicle since receiving your help suggestions, but I hav... Trouble codes: U0073 (Control module communication BUS off), U0100 (Lost communication with ECM/PCM), U0140 (Lost Communication with BCM), P0700 (Transmission control system fault).
1993 Oldsmobile Cutlass Supreme 3.1L Poor Idle Quality VIN: 1G3WH54T9P
IATN members ROCK!!. I got 14 replies to this post in 72 hours. All were excellent. Don, Joe, Warren, and John had the info that ended up helping me repair this one. Aldata spect TPS voltage at 8. After drilling the TPS mounting hoes out a bit, and setting it ... Trouble codes: 35 (Idle control problem).
2009 Pontiac Vibe AWD 2.4L abs light VIN: 5Y2SM67079
I replaced the battery and have not heard back from the customer so I am gonna call this one a fix. Suspect loose plates in the battery.
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