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International Automotive Technicians Network
Prev Professional Automotive Repair Technical Discussions for September 23, 2009
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Open Help Requests for GM
Help Request Answers
1985 Buick Regal Grand National 3.8L Electronic VIN: 1G4GK4791F
the car came in with a soft brake pedal.i bleed the system and checked the adjustment. everything was ok. test drove car andwhile braking the pedal fades. ckecking the car the pump motor keeps running all the time. turning the key on the pump motot powers up d...
1989 Buick Century Custom 3.3L No Start VIN: 1GA4L51N5K
help,help ,help,this car is blowing me away,this car sometimes has no injector pulse,i checked crank signal at computer and fine,all the grounds tested good i even clean the base of the ignition module,connect scaner shows rpm,no codes are set,replace new cran...
1993 Buick Regal 3.8L No Start VIN: 2G4WB54L8P
cust states wont start intermitten ,i have not been able to verify .cust said tried to start ten times with no suscess,just cranks. when fuel pump was replaced in jan ,i got the wrong pump from parts house at first ,then was given one that bfit but was not the...
2000 Buick LeSabre Custom 3.8L radio door locks a/c VIN: 1G4HP54K3Y
hello need help . 2000 lesabre upon starting vehicle after say 5 or 6 seconds. radio goes out. door locks inop.security light comes with airbag,brake,service vehicle soon traction control light's gear indicator numbers light up but will not indicate gear posit...
2002 Buick Rendezvous CX 3.4L LF wheel sensor VIN: 3G5DB03EX2
left frt wheel speed sensor triggering a code 3 bearing assemblies latter no progress see my repair history and get an understanding of my problem. thanks for your help
2002 Buick Century Custom 3.1L abs VIN: 2G4WS52J82
I'm here asking you guys for your input. Last month we serviced this vehicle for a stored C1225 code-left front wheel excessive speed variation. We scoped the front sensor and test drove the vehicle to confirm several small voltage spikes-violla! Seemed pretty...
1985 Chevrolet C10 Scottsdale 5.7L Mechanical VIN: 2GCDC14HOF
Question for the transmission gurus on a 700R4...I have a local young lad who is slowly assembling this old truck. He got a used trans that was apparently rebuilt 16K ago and put it in. Immediately it does what his old tranny did...slips in anything over secon...
1995 Chevrolet K3500 Silverado 6.5L none VIN: 1GBJK34F8S
Hope someone can help, i just replaced injection pump on this truck,there is no problems, it starts and runs fine, I just need to know if anyone knows if you can set timming with a OTC GENYSIS? I had a tech 2 that I have used to set it before, but it is being ...
1999 Chevrolet K3500 5.7L fuel gauge VIN: 1GBJK34R7X
Anyone know what the reading is coming out of the balance module going to the VCM, and out of the VCM to the gauge? We have voltage coming out of the balance module (4.1v), but believe we are supposed to have resistance (average of both senders). Bench teste...
1999 Chevrolet Corvette 5.7L Running lights VIN: 1G1YY12G9K
Hello Gents we have no running lights on this vette. first thing we looked at was the body control mod. It shows the headlight switch turning on and off but no running lights. Next step check all fuses. All ok. Next relays. All good. My next move was to check ...
1999 Chevrolet Silverado 2500 6.0L Low speed ABS activation VIN: 1GCGK29U7X
Hello All, I have a low speed ABS activation on moderate braking that was doing this BEFORE any work or tires were done. I have scoped wheel sensors (800mV even side to side) checked wheel bearings and inspected mounting surfaces. The scandata shows 1 -3 MPH ...
1999 Chevrolet Silverado 2500 LT 6.0L Hesitation VIN: 1GCGK29U4X
This truck has a hesitation when pulling away from a stop. We cleaned the throttle body (really dirty) and maf sensor, re-flashed computer. During light load cruise the fuel trims are at +25% the entire time and are in the positives all other times. We have ch...
2004 Chevrolet Cavalier 2.2L No Start, MIL Lamp on VIN: 1G1JH12F84
Hello fellow techs, This was brought in as a no start, customer drove it in. Along with the codes listed, the head scratcher is that the milage currently states 18426 miles. At 6/5/08 we did service, the milage was 66233. The current oil change sticker on the... Trouble codes: P1631 (Theft-Password incorrect), U1064 (Loss of communication BCM/DIM/SBM), U1000 (Class 2 data link fault), B2960 (Passlock cylinder data incorrect), B1000 (ECU malfunction)
2007 Chevrolet Monte Carlo LT 3.5L MIL Lamp on, Reduced power. VIN: 2G1WK15N97
Vehicle is salvaged. Customer pulled code P2135 and replaced the TAC with one from a wrecking yard. Same code with both units. I have scoped both TPS sensors KOEO and get a good waveform and low voltages (.8V), but according to Mitchell I should see at least 4... Trouble codes: P2135 (TPS Sensor 1-2 correlation problem.), U0140 (Lost communication with BCM.)
1994 GMC Jimmy 4.3L No Start VIN: GKDT13W9R2
vehicle was tow in ,no start condition,costumer replaced cap rotor,installed wrong,he was triying to start,we checked fuel presure is ok 60 psi,holding ,replaced spider unit was leaking not luck,vehicle was also flooded replaced spark plugs,compresion at 120 p...
2002 GMC Sierra 3500 SLT 6.6L flywheel cover VIN: 1GCJK33162
We found a coolant leak near the back of the left cylinder head and determined (after a lot of exploratory surgery) that we needed to remove the flywheel cover, as the leak appeared to be coming from that area. After removing the transfer case and transmission...
2003 GMC Envoy XL SLT 4.2L battery VIN: 1GKET16S53
Thank you in advance for your help. This 03 Envoy keeps killing the battery when allowed to set over night. we have tested the vehicle and isolated the problem to the items controlled by fuse 35 in the under hood fuse box (40A) Blower motor. This goes to the B...
2004 GMC Sierra 3500 6.6L fuel gauge VIN: 1GDJC34264
fuel gauge reads empty low fuel lite on.Install new front tank and sending card,few months later same problem,so we put a new fuel tank in rear and new sending card also, 1 day later gauge goes to empty and low lite back on, and yes tanks are full when this ha...
2002 Pontiac Grand Prix SE 3.1L no start, left blinker light on steady, VIN: 1G2WK52J32
during test drive from previous repair, stopped at a store, shut engine off and removed key. came out of store and noticed left front blinker light on steady, blinker indicator on dash on steady. coolant light on and oil pressure light flickering. engine crank...
2004 Pontiac Grand Prix GT1 3.8L High gear starts VIN: 2G2WS52284
This vehicle, when cold, will have a high gear start ( 3rd or 4th ) for about 1-10 feet, then drop into 1st, and shift normal until you come to a stop, then it may repeat for the first 4-5 shift cycles, then seems to work fine. Scanner shows a command for 1st ...
2005 Pontiac Aztek 3.4L horn VIN: 3G7DA03E45
Does anyone out there know where the right side (High Note) horn is located? No problem finding the left one. But unable to locate the right one.

Fixes & Summaries for GM
Fix/Summary Answers
2003 Cadillac CTS 3.2L Poor Idle Quality, Misfire VIN: 1G6DM57N13
Hello all.. Thanks for all the positive feed back!! During diagnostics found the right bank running rich at idle, which lead us to believe that cam timing was out. The problem actually ended up being, a mouse got into the front cover and got caught in the timi... Trouble codes: P0300 (random misfire), P0301 (cyl 1 misfire), P0303 (cyl 3 misfire), P0305 (cly 5 misfire).
1991 Chevrolet S10 Blazer 4.3L No Start VIN: 1GNCT18Z2M
Well this one is down the road. It was the white EST wire from the module to the ECM shorting on the engine lift bracket. The reason I didn't get this right away even though I had seen it in the archives was that the short had burned the ignition coil windin...
2001 Chevrolet Blazer LS 4.3L Engine VIN: 1GNDT13WOX
Hi fellow head bangers. Many thanks to all who responded with loads of good ideas. As Arrow & Scott said cranking voltage was not good so we fitted new battery, Crank volts excelent. Now customer tells us that vehicle stops while driving it & will not start, s...
2002 Chevrolet Silverado 1500 5.3L Drive-axles VIN: 2GCEK19T22
Thanks for all the help. It does turn out that I am chasing a ghost. I compared a truck that was the same and it does the same thing. Thanks again for all the help. Mike
2003 Chevrolet Silverado 1500 4.8L Surge, Misfire VIN: 2GCEC19V83
Thanks for all the great tips. The customer had to take vehicle, he put his factory air breather back on, after the lecture about the K & M filters and MAF issue. Then it would not start. Towed in. I saw some wires that looked like they had been tampered with ... Trouble codes: P0172, P0175, P0300.
1996 Oldsmobile Cutlass Supreme SL 3.1L MIL Lamp on VIN: 1G3WH52M9T
had pcm programed to vin and everything operating correctly Trouble codes: P0336, P0171, P0101.
2005 Saturn Vue 3.5L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire VIN: 5GZCZ53495
I must say... this makes no sense. After checking EVERYTHING which was mentioned in posts and ending with no diagosis... I cleared codes. Drove... let it act up and came back with the cam and misfire code every time. I had the ignition, primary, cam and cra... Trouble codes: P0341, P0300, P0303, P0580.
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