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2003 Cadillac DeVille 4.6L Poor Idle Quality, Stall, Misfire
G.M. Techs your knowledge is needed.I have lost my --- on this one. Did have a bad vaccum leak,quick bucks, yea right 5 days later,1-3-5-7 missing randomly,compression chk. all above 140. Found T.S.B. on reprogram called dealer been done, hoping to pawn it on ... Trouble codes: p0171b (p0174b-), p0174b (p0300b-), p0300b (p0506b-), p0506b (p0507b-), p0507b (testing and results).		 View
2004 Cadillac SRX 4.6L loss of assist
Customer has left vehicle with us twice, but we have not been able to verify symptom. Customer says total loss of power assist in both directions. engine speed is not a factor. We have been road testing for several days and not been able to verify any problems...		 View
2004 Cadillac CTS 3.2L Starting
Hi, I have cad. that when in cranking possion will pulse voltage to starter,check engine light & interior light flash with pulse also. battery & connections are good.no engine codes will loose communications with pcm when cranking. tested fuses & relays, good....		 View
1987 Chevrolet Corvette 5.7L Poor Idle Quality, Surge, Cuts out, Stall
i have this 87 corvette in my shop that runs kinda weird and gives me weird mass air flow data. customer complained of running rough, check engine light on and said if he shut it off and restarted it that it would run fine for about 60 seconds before running r... Trouble codes: 34 (mass air flow sensor).		 View
1995 Chevrolet Camaro 5.7L top end
hi people here is my situation.this car had head gasket failure,we replaced head gaskets,took the heads to our local machine shop where they took out the bad spot surfaced both heads pressure checked them and "cleaned up the valves"according to the machinest ...		 View
1996 Chevrolet Pickup 7.4L MIL Lamp on
Hello Chevrolet/Gm techs.. I'm almost exclusively a Ford shop but we have a 96 3500 series 7.4 in our fleet that runs like a 'swiss watch' at all throttle angles/loads.. We're trying to get thing past CA smog to sell/auction it, but it keeps setting P0300 for... Trouble codes: P0300 (Random Misfire).		 View
1998 Chevrolet Pickup 5.7L range hub
This truck came in with a noise on decellaration it was diagnoised to be in the transfer case. The range fork was worn severly and range hub had contacted the planet and rounded the teeth. We replaced the fork, hub, and planet and reassembled. Truck came back ...		 View
1999 Chevrolet Lumina 3.1L Surge
Car came in for heater hoses due to leak. Repaired them and test drove fine. Customer came to get and tried to back out of the parking sopt and the thing started to buck and surge real bad. The next morning tested and it runs great for about 2 minuets and then... Trouble codes: p1106 (Map voltage intermiten high).		 View
1999 Chevrolet Corvette 5.7L MIL Lamp on
thanks for all your help Trouble codes: p0327 (knock sensor signal 1 front signal).		 View
2000 Chevrolet Impala 3.4L High idle
This vehicle came in originally for an intermittent stall. Checked IAC motor and found it sticking. Replaced and cleaned out throttle body. Came back a while later still stalling and now with TP sensor codes and a MAF sensor code. Tested and replaced MAF senso... Trouble codes: P0122 (TP sensor signal low voltage), P1122 (TP sensor signal intermittent low voltage).		 View
2001 Chevrolet S10 Pickup 2.2L Hesitation, Cuts out
Hello to All, Here is how the customer describes his issue,"hesitation when leaving off gas & when stepping on the gas slightly.Feels like ignition misfire".Owner has replace plugs, wires & coils with no improvement.I could not duplicate these symtoms, howev... Trouble codes: P0122 (TPS sensor cicuit lowshort).		 View
2002 Chevrolet Venture 3.4L No Start
Van has sat for a year. Only code is p1189 eop sensor. Van will crank but no start. I have 60 lbs fuel pressure, good spark, I believe no injector pulse. I can run an injector balance test with MODIS and van will then try to start then die due to fuel injector... Trouble codes: p1189 (engine oil pressure sensor).		 View
2003 Chevrolet Express 6.0L Misfire, MIL Lamp on
We got this vehicle in for check engine light codes p0300 multiple cyclinder miss fire and code p0340 catalytic effiency bank 2 check cat post o2 sensor voltage varrying from 200 to 800 mv same as pre o2 sensor we are recommending cat. check code p0300 check m... Trouble codes: p300 (multiple cylinder miss fire), p430 (catalytic converter efficency below threshold).		 View
2003 Chevrolet TrailBlazer 4.2L MIL Lamp on
Purge solenoid and vent solenoid tested OK. Unfortunatly don't have smoke mashine. Any common problem,any ideas? Trouble codes: PO442 (Small EVAP leak).		 View
2004 Chevrolet Silverado 4.8L Engine
Customer complained of engine noise at startup when cold. It sounds like lifter noise and more than just one. The oil pressure is good and due to the low mileage on the truck I need help from Chevy techs to know if theres any problems mechanically with this pa...		 View
2004 Chevrolet Impala 3.8L No Start
Vehicle driven in once, towed in second time for intermittent crank/no-start. She states the security warning flashes, she can duplicate the problem using the remote unlock feature but she can't prove it here. She also claims to be able to start it most times ...		 View
1997 GMC Pickup 5.7L No Start
keeps burning connector at sender inside tank. fuel filter has been changed , i cked this time & it's clean, tank is clean ,the sock was like new. cked voltage at fuel pump getting 12.1-12.2v tried another relay voltage unchanged. running v are 13.2-13.5v		 View
2002 GMC Yukon 6.0L heated seats
thanks in advance for any help with this one, i have a denali whith inop heated seats, both front. i have tested all wiring and switches to to seats, and all work fine. so now iam at the point alldata says to test the seat element ( back) for resistance. wirin...		 View
2002 GMC Yukon 6.0L heated seats
thanks in advance for any help with this one, i have a denali whith inop heated seats, both front. i have tested all wiring and switches to to seats, and all work fine. so now iam at the point alldata says to test the seat element ( back) for resistance. wirin...		 View
2002 GMC Envoy 4.2L abs
replace air suspention compressor and that fixed air suspention. I have a abs light and red brake light on . also service brake message on dash along with no speedometer and no transmission shifting. codes co236 and po502 present . speed sensor and abs speed s...		 View
2002 GMC Savana 6.5L No Start
Need some help from all the 6.5 experts. This van belongs to a personal friend.Started out on a road trip it it and over heated.(Having to put 30 gallons of water in it to make it 50 miles back home) When it was towed in I found 3 cylinders hydro locked. I rep...		 View
1990 Oldsmobile Toronado 3.8L Poor Idle Quality
This car has been nothing but problems. The car has a problem keeping the idle that has been learned. Customer recently purchased it. It originally came in on the hook. Intermittent no start, replaced the ICM, and that fixed that problem. After it was started ...		 View
1991 Oldsmobile Ninety-Eight 3.8L ign spark
customer brings car to me and says intermitantly car dies while driving. Sometimes it will restart right away, sometimes takes several minutes to several hours to restart. Fuel pressure ok always. took 2 days to recreate symptom in shop. tested and replaced cr...		 View
1999 Oldsmobile Alero 2.4L Misfire
Thanks in advance. This is one those problems . A quick run down, the cust came in months ago with a nostart, I spent hours on it and it had no spark,after much testing (coils module etc) I gave up and sent her to the dealer. and never heard from her again. No... Trouble codes: P0304 (4 cyl misfire).		 View
1997 Pontiac Trans Sport 3.4L wipers
we have installed a wiper transmission last winter. the wipers froze to the windshield and won't park. last week it came back not parking again. we started with another transmission ( the part that looks like a rachet) we set it like gm says then activate the ...		 View
1999 Pontiac Grand Am 2.4L engine
I have a 99 Grand Am with a once in a while no start,setting 2960 code in theft system.From my experince,passlock sensor is the problem,vehicle is my daughters car,was wondering if anyone has experience bypassing this type of system.On the older systems I have...		 View

Fixes & Summaries for GM
Fix/Summary Answers
1997 Buick LeSabre 3.8L fuel gauge
IT APPEARS THERE WERE 3 DIFFERENT TYPES OF GAUGES USED, AND THREE DIFFERENT WIRING DIAGRAMS. THE CAR COMES BACK IN TOMORROW, AND WE WILL TRY TO MAKE SENSE OF IT AGAIN.		 3
1998 Buick Regal 3.8L heater blower motor
Thank you for the coherent replies. (Not check power and ground)This is how it went down. The dealer does not have or supply a compatible blower motor for this vehicle. We did locate a blower motor kit which contains the motor, vent tube, under dash panel, 3 p...		 8
2002 Cadillac Escalade 6.0L rpa system
WELL AFTER READING MORE ABOUT THIS SYSTEM THROUGH MITCHELL ON DEMAND I WAS ABLE TO UNDERSTAND THE SYSTEM AND RETRIEVE CODES. ALLDATA WAS NO HELP AT ALL!! AFTER GETTING CODES I WAS ABLE TO DETERMINE THAT LEFT REAR MIDDLE SENSOR WAS THE ONE THAT SHUT DOWN THE SY...		 3
1989 Chevrolet Pickup 5.7L Poor Idle Quality, Surge
To answer a few replies, the fuel pump (pressure and volume) was good, also had a good waveform and good pump speed. I hooked up a fuel injection cleaner machine to remove the fuel pump from the system and I still had the problem. Everything was pointing to ...		 16
1989 Chevrolet USPS LLV 2.5L No Start, Stall
Thank you for all your help. As it turns out, it was the fuel injector. It would operate at under 13 volts, even through receiving proper voltage and trigger. Replaced the injector and it runs like a charm!		 7
1998 Chevrolet Blazer 4.3L Fuel gauge,low fuel light, battery light
Good morning gentlemen. I'm happy to say this one is fixed. The problem was the brown wire from the 4wd fuse to the front diff actuator would sometimes pinch in the steering u-joint that was missing it's plastic cover.I didn't spot where this wire even existed...		 6
2001 Chevrolet Silverado 6.6L transmiision, speedo cluster
REPLACED IGNITION SWITCH AND NOW WORKING AS IT SHOULD, WE WERE ONLY GETTING 10.6 VOLTS TO TCM AND WHEN REPLACED SWITCH WENT TO 12 VOLTS, THANKS FOR ALL THE HELP		 5
2002 Chevrolet Express 5.7L hard start
Fixed the van yesterday. I found out fuel was leaking from the injector area at the rear. May have been a line, seals, or an injector. We changed the rear 4 injectors and the seals to the other 4 injectors, fuel meter, and the regulator. It always started r...		 8
1996 Geo Tracker 1.6L MIL Lamp on
Thanks for all your help, made the mistake of not looking down the throtle body at the hole in the intake, intake was almost pluged. Thanks to all that helped. Trouble codes: P0400 (egr flow).		 6
1998 GMC Pickup 6.5L Cuts out, Stall
thanks to all who replied when we rescaned vehicle after it wou consisiently quit in parking lot we had a code 1216 .replaced injector driver kit and all is working fine. thanks again you guys are a great help 		10
2000 Oldsmobile Intrigue 3.5L Engine temp
The fix for my overheating problem was the updated T-stat from GM. Thank you to those of you who replied to my posting. 		5
1998 Pontiac Sunfire 2.2L abs
Thank you, John from Georgia. He sent a publication which described how code 86 was displayed as C1286 for 97/98 models. It explained that the gears were binding in the motor pack. Checked and confirmed. Motor pack replaced with used unit. All functions good, ...		 4
1999 Pontiac Grand Prix 3.1L Heater Fan
I would like to thank, Murray, Robert, Jason, Paul, & Kim, for pointing me towards the Ignition switch. I also would like to thank Terry, who gave me a simple check to determine the problem, which was (check the voltage to your hvac fuse.you will probably fin...		 10
2000 Pontiac Montana 3.4L power sliding door
I pefrormed the relearn and found the motor shorted and bad I replaced the motor and performed the relearn to fix it		 7
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