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Prev Professional Automotive Repair Technical Discussions for March 19, 2008
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Open Help Requests for GM
Help Request Answers
1995 Buick Park Avenue 3.8L Instrument cluster & HVAC VIN: 1G4CW52K5S
When I got the vehicle in I put my fault finder in the circuit and found nothing. Installed new fuse and road tested. Never did feel an engine miss. Everything is still working. This fuse controls the instrument cluster, door chime & info center according to t...
1980 Cadillac Seville 5.7L horn inop VIN: 6S698AE690
i need some help finding the horn relay, i have no older books , all wiring seems in place and i cant find the relay under the hood. thanx in advance for any help!!
2000 Cadillac DeVille 4.6L controls VIN: 1G6KD54Y7Y
Hi guys hope you can help. I have 2000 Deville with no heat coming out of the pass. or rear vents.Stays cold all the time.Drivers side works fine, I scanned with snap-on 2500, but can't access the hvac computer.I have a feeling its an actuator based on what i'...
2004 Cadillac Escalade EXT 6.0L Sound System VIN: GYEK62N44G
Hi everybody, i have sent a post before about this car regarding the sound system, there was no sound so i ordered a new sound amplifier and fixed it, now there is sound from the music system but only from the right front speaker, left front and both rear spea...
1992 Chevrolet Corvette 5.7L No Start VIN: 1G1YY23P7N
This car was towed into our shop and would not start, cranks fine,this car has no communication with scan tools, no spark, have tried a new ignition module and new distributor and still have no spark have checked all power and grounds at the ECM
1993 Chevrolet Corsica LT 3.1L Poor Idle Quality, Hesitation VIN: 1G1LT553T1
Good ol GM. This is our shop car and we are in dire need of some help. At start up she runs fine. Great in fact, but after about five minutes it begins to idle real rough and hesitates. Checked over injectors and found a bad injector, replaced and this fixed i...
1994 Chevrolet Astro 4.3L Hesitation VIN: 1GLDM15Z5R
This Astro Came In Today With Complaint Of Hesitation/Bucking Under Acceleration, Check Engine Light On.Has Code 43 ESC Module Or Sensor Circuit Problem.When I Looked Up In Alldata They Just Say To Test Knock Sensors (Snap On Troubleshooter Says The Same Thing... Trouble codes: 43 (esc module or sensor circuit problem)
1995 Chevrolet Monte Carlo Z34 3.4L timing belt VIN: 2G1WX12X4S
This car came to us about 5k miles ago w/ a new t-belt, tensioner pulley and both idlers new, not running. Engine was out of time. Re timed and then found a non sealing valve. Did the heads and reinstalled w/ new parts. Re-used the Dayco brand parts listed abo...
1996 Chevrolet C1500 Cheyenne 5.0L Control Head VIN: 1GCEC19M0T
Replaced this control head twice over the past 6 months. Each time the blower will not operate. New head takes care of customer complaint. No signal from head to relay to close. Did not find any related posts in archives. What should I look for in harness to f...
1999 Chevrolet K1500 Suburban 5.7L Misfire VIN: 3GNFK16R9X
a mechanic friend replaced lower intake gasket and water pump and now is misfiring on cylinder #8. tried different plug wire same problem also checked with intake cleaner for vacuum leak around plenum and intake. he said he did have the poppets out of the hole...
2000 Chevrolet Impala 3.4L Fuel Gauge VIN: 2G1WF55E3Y
This one has got me stumped. Hope someone can help. Fuel gauge reads steady and accurate with the key on or vehicle running in the shop. If you begin to drive(forward). The fuel gauge will rise to about 3/4 of a tank and bounce around. Sometimes if you are at ...
2001 Chevrolet Impala 3.4L Hesitation, Poor Fuel Economy VIN: 2GIWF52E21
Hello this is my own vehicle the problem on this car, every time that I step on the gas pedal my car does not respond like it should all I heard is like a buzz in the intake (throttle) and it takes me a while to pick up speed does not misfire this morning fina... Trouble codes: P0404 (egr open position performance)
2005 Chevrolet Impala 3.4L srs lamp on VIN: 2G1WF52E35
B0022 is low resistance on stage one drivers air bag ckt. DVOM test shows same resistance on both stage 1 and two with no shorts between as suggested. We had a2004 on hand so I swapped drivers bags and the code B0022 stayed with the 2005. Disconecting restrain...
2002 GMC Safari SLE 4.3L MIL Lamp on VIN: 1GKEL19X02
2000 miles ago engine had a knocking from the oil pump when cold, found a sludge residue in bottom of pan and radiator was low on coolant. (oil is changed every 3000 miles and fluid checked religiously since new) at that time oil pump was replaced along with h... Trouble codes: P0300 (random missfire), P0335 (testing and results)
2000 Pontiac Grand Am GT 3.4L Misfire, MIL Lamp on VIN: 1G2NW12E7Y
As you can see in the history we been at this car for a long time, very little mileage driven. Hesistation and MIL issue. Have ramp tested injectors all pass, except the one we replaced #6. complression on engine good, ignition system new. Delco parts. Fuel pr... Trouble codes: P0300
2001 Pontiac Bonneville SE 3.8L fuel gauge VIN: 1G2HX54K11
Hello Group, I have this Bonneville fuel gauge will sweep to full when started then after about 20- 30 seconds goes to empty and stays there until the key is cycled off then on and repeats. Scanner says level at 199% regardless of unplugging sender at the tank...
2003 Pontiac Grand Am SE2 2.2L No Start, Stall, DUMPS FUEL VIN: 1G2NF52F43
changed oil/spark plugs/crank sensor. checked fuel presure ok/ did all ign tests for coils ok/no codes/batt dead when we got car/ will start & almost run for 3 sec dumps fuel like giant insect fogger/ replaced map sensor/ checked tp voltage ok/ ect & act are o...
2001 Saturn L300 3.0L motor mount? VIN: 1G8JW52R01
Last week we put a timing belt and water pump in this car. Sence then it clunks when it up-shifts. It is at it's worse during light acceleration 1 to 2 upshift. I adjusted the upper motor mount a few days ago and it cured the problem for a few days. I have no...
2001 Saturn SC1 1.9L high idle VIN: 1G8ZN12801
This vehicle came in with an intermitten high idle at stop from cruise speed, about [...] when stopped. checked the IAC counts, 15. Sweeped TPS, OK. And cleaned throttle plates. Pulled DTC's P0122,P0507, and P1599, I need some help with this one, Thanks. Trouble codes: P0122 (TP sensor circuit low voltage), P0507 (idle speed high), P1599 (engine stall)

Fixes & Summaries for GM
Fix/Summary Answers
2002 Cadillac Seville STS 4.6L No Start VIN: 1G6KY54912
Allright this one wasnt a power or ground issue. I traced all powers and ground to the pcm..all were good. i the cut the two data link wires that link the engine computer to the other various computers.. i then clipped the data wire at the data link connector ...
2003 Cadillac CTS 3.2L MIL Lamp on VIN: 1G6DM57N93
I checked a vac line that runs from the back drivers side of the engine to the coolant bypass valve and it was off at the engine side i put it back on and it left only to come back again a week later with same symtom. I looked at the line only to find it was o... Trouble codes: P0128 (coolant temp below t-stat regulating temp).
1993 Chevrolet C3500 Cheyenne 6.5L No Start, Poor Idle Quality VIN: HC39F3PE24
First off, thanks you for all of the replies I received. There were a lot of suggestions on how to determine if the injection pump was faulty. The best suggestion was to remove the cold advance solenoid and listen for a change in the sound of the engine idling...
1994 Chevrolet S10 2.2L no power VIN: 1GCCS1449R
Replaced Cat, Still had problems with power, The cat was a straight unit so I was able to easily look inside it. It was without question clogged. The guts were smooth and looked to be in tact, Thats were I went wrong. Even though it appeared to be intact peice... Trouble codes: 44 (Lean exhaust).
1995 Chevrolet K1500 5.7L light burning VIN: 2GBEK19K4S
First of all i want to thank every body for helping us FIX this truck. Two of you nailed it right on the head about what was wrong with the transmission and the speedometer. The ignition switch was bad and would not let the transmission shift gears and the ...
1998 Chevrolet C1500 Cheyenne 4.3L No Start VIN: 1GCEC14W9W
Thank you everybody who replied. I put a valve inline in the return line to test pressures. With it shut off, engine not running, I could only get 55 psi. I replaced the fuel pump and it took care of the starting issues. I wasn't aware how critical the fue...
1999 Chevrolet Silverado 1500 4.3L Misfire, MIL Lamp on VIN: 1GCEC14W2X
Not able to post a fix just yet, customer to take vehicle as is and come back in a month. What I did find is that the IAC counts are in the normal range 35+or-. The fuel trim numbers for both banks are in the 130 range. Motor is running alittle lean. On start... Trouble codes: P0300.
2002 Chevrolet Cavalier LS Sport 2.2L Poor Idle Quality, Surge, Stall VIN: 1G1JH12F52
Well this one is fixed. After pulling the fuel rail to visually inspect the fuel injectors and their o-rings I was on the phone to our parts supplier attempting to get new o-rings for the injector. As he described the injector and what the o-rings looked like... Trouble codes: P0172 (Fuel system rich History Code).
2001 GMC Yukon XL 1500 Denali 6.0L oil pump VIN: 1GKFK66U11
all the testing i did kept pointing to the oil pump,but could be etched in stone. i consulted some g m engineering friends of mine and explained the problem i was having.they assured me it was in fact the oil pump.they have seen a lot of these problems, even d...
2003 GMC Sierra 1500 SLE 5.3L MIL Lamp on VIN: 1GTEK19TX3
The problem was at the pcm blue connector pin 23 that is the ground for the sending unit i had 5 volts on the purple wireand 5 volts on the return black wire i unbolted the connector and put some dilectric grease on the terminal and bolted it back up and the g... Trouble codes: 461 (fuel level sender), 463 (fuel level sender volts high).
1995 Oldsmobile Cutlass Ciera 3.1L service engine soon VIN: 1G3AJ55M05
hello thanks for the help. I cleaned the hell out of the egr ports and all is well. This one is fixed! thanks again Trouble codes: 1405 (egr solenoid error).
1994 Pontiac Grand Am SE 2.3L No Start, Cuts out, Stall VIN: 1G2NE5533R
1995 Pontiac Grand Am SE 2.3L Excessive Emissions, Poor Idle Quality, Misfire, Poor Fuel Economy VIN: 1G2NE55025
Thanks for all of the great help. It turned out that the ignition housing was bad. It had a short between cylinders 3+4. It showed 60K ohms. Tried a new one and after the cylinders cleaned up it runs great now.
1998 Pontiac Sunfire GT 2.4L air in hydraulic system VIN: 1G2JD12T6W
The customer hasn't been back for three weeks, its either fixed or he traded the car off. Replacing the slave and master with GM parts seems to have fixed it. A bad rap for aftermarket, I promise I wont tell any dealership guys about this one. Thanks to all wh...
2001 Pontiac Montana 3.4L MIL Lamp on VIN: 1G5839T452
michael from new york hit the nail on the head was just another problem. somtimes weall look to deep into things lots of good post the other on was broken wires at the pcm i didnt have any but well no to look there with other electrical problems thank IATN mem... Trouble codes: P0102.
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