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Open Help Requests for GM
Help Request Answers
1989 Buick LeSabre 3.8L a/c
we have zero cooling the evap core has been removed and cleaned we can not find an orifice tube anywhere in the system and the pressures are around 35-40 and high side is 200-250 with no coolong taking place. What am I forgetting also where should the orifice ...		 View
1997 Buick Skylark 2.4L heater core
I have a 1997 buick skylark with a 2.4 quad 4 cyl in the shop for the 3rd time in 12 months with a leaking heater core. I have replaced the core 2 times before and each time it has been pin holes in the core due to what i belive to be "electrolysis" I have tes...		 View
1998 Buick Park Avenue 3.8L ignition
it starts at times and the temp has nothing to do with it because when its cold over night no spark,when its 100 degrees no start,no spark,this morning it would`nt start,moved module wires a little and it started.code po107 and has slow timing after it starts ...		 View
1999 Buick Regal 3.8L Suspension
it has a clunking noise at accel and at stop in the right front. i have replaced both lower motor mounts, both front wheel bearings, front brakes, right front lower control arm with the bushings and balljoint,and have had the cradle loose greased the bushings ...		 View
2001 Buick Regal 3.8L blower
hey fellows i got a buick regal that the custumer states that the blower works when it wants to i never was able to duplicate the problem so on a whim i instaled a gm blower resister now weeks later the car is back and this time no blower the first thing i did...		 View
1989 Cadillac Eldorado 4.5L Poor Idle Quality, Hesitation, Stall, Misfire, hard start
Hello Cadilac techs. I have a 1989 elderado that is have issues starting and has an extreamly rich idle. Using a snap on scan tool I determand that the computer was not getting an input from the colant temp sensor mounted on the back clyinder head. I have test...		 View
1992 Cadillac DeVille 4.9L Poor Idle Quality, Cuts out, Stall, Misfire, MIL Lamp on
This Cad. come in for diagnostic stalling vehicle run a little rough. This Cad stall at idle. Found code 71 intermittent MAP problem. I did change new MAP but same problem. I reset computer let it run at idle for 25 min. I notices sometime at idle vehicle rpm ... Trouble codes: 71 (intermittent manifold absolute pressure), 52 (Electronic Control module reset).		 View
1999 Cadillac Eldorado 4.6L hvac
Need help. 99 Cad that after running AC system defaults to defrost. It does return to vent by it's self. Does it most when hot. When testing all ok. thanks		 View
1995 Chevrolet Lumina 3.1L Battery
Good afternoon fellow members. I have a real head scratcher here. Customer came in about 4 months ago with no turn signals, found the switch was bad, replaced switch. About a month later he called and said the battery was dead after sitting a few day, so he ch...		 View
1997 Chevrolet Cavalier 2.2L cooling
Help. Got this calvalier from 2 other shops, It is running about 215 to 225 degrees. It had a head gasket put in in Aug. 2008 and as far as I know the head was checked and plained. It also has a new radiator and water pump. Full of clean anti freeze. Right now...		 View
1998 Chevrolet Malibu 3.1L compressor
Hi all, this malibu blows the 10a compressor fuse. ive checked wiring to compressor clutch and resistance accross clutch 2.5 ohms.I have upped the fuse to 20a and the problem as i see it is that the headlights ( and parking lights) come on when ever i put that...		 View
2001 Chevrolet Malibu 3.1L No Start
have replaced the fuel pump three times. need help		 View
2001 Chevrolet Blazer 4.3L left side motor mount
vehicle came in with clunking noise up front.i can not see it but i beleive left side motor mount is broken.when you brake torque vehicle engine lifts up on left side.can anyone give me the correct procedure for replacing left side motor mount.any help would b...		 View
2003 Chevrolet Cavalier 2.2L Mechanical
We have one that is driving us nuts! Towed in for a no start in March, no fuel pressure, replaced the pump. No start at times again early June, good fuel pressure, replaced crank sensor, all was well. Back 2 weeks later same issue, crank, no start, has fuel pr...		 View
1992 GMC Pickup 5.7L Hesitation, Cuts out, Stall
Thanks in adv ance for all your help. After used engine installation,this truck will stall at idle. Fuel pressure at idle is 15 psi, LTFT 110, STFT128. After fuel return line is pinched truck runs great and fuel pressure jumps to 20 psi. Map sensor readings at...		 View
1995 GMC Vandura 5.7L MIL Lamp on
The engine starts and runs at a high idle. Check engine light stays on. Cannot scan PCM. When you drive vehicle it starts out in second gear shifts into 3rd but will not shift into overdrive. Have tried two different scanners neither will communicate with PCM....		 View
1999 GMC C3500 HD 6.5L No Start
hey guys thanks in advance. truck came into shop with engine knocking so we replaced it with a known good one. exept the darn thing won t start. new crank sensor ,we switched injector control module ,even put in the pump from the other engine. i have 5 volt re... Trouble codes: p0335 (ckp sensor circuit performance), p1631 (theft deterent password incorect).		 View
2003 GMC Sierra 4.8L gauges
Hi. did some work on this truck and the battery went low from the key being left on, jumped the truck and proceeded to finish things up. now the gauges dont work. Interfaced with the ipc, saw a bus communacation code . cleared the codes, i can command the tale...		 View
2003 GMC Envoy XL 4.2L strong odor
is it possible that the tank pressure sensor on top of fuel tank module has started leaking.even when she fills the tank it leaves no puddles.		 View
2001 Pontiac Bonneville 3.8L MIL Lamp on
Hello, all you GM Techs,i have a problem child here. I have a reading of 1.45 volts at the fuel pressure sensor pid. I have smoked vehicle and came up with no leaks,snap-on machine ran test and says it is holding vacuum.i have vacuum at canister all the time a... Trouble codes: p0452 (fuel pressure sensor short to ground), p0440 (evap sys problem).		 View
1992 Saturn SL 1.9L MIL Lamp on
CUSTOMER COMPLAINT IS THE CAR WON'T SHIFT INTO 3RD GEAR OR GO OVER 35MPH.AFTER A TEST DRIVE,FOUND THAT THE ENGINE LACKED MAJOR POWER, BUT WOULD SHIFT INTO ALL GEARS IF YOU WAITED LONG ENOUGH.WHEN YOU HAVE THE CAR IDLING AND NOT IN GEAR AND YOU GIVE IT GAS,IT R... Trouble codes: 26 (quad driver problem), 53 (info flag esc exceed max valvue).		 View

Fixes & Summaries for GM
Fix/Summary Answers
1994 Buick Century 3.1L No Start, Stall
Thanks for all the replies, I had done all that and was frustrated that I could not find anything. I worked on it last night while nobody was around to distract me and I found it. broken ground in trunk on drivers side on wheel well. When I would hook up the p...		 27
1995 Buick LeSabre 3.8L Electronic
thanks to all that sent help. I took a closer look at all the input to pcm found the IAC motor was high then after playing with throttle notest motor was not moving. the funny think is it seem to idle fine. I replaced the IAC motor it fixed the problem. thanks...		 8
1997 Cadillac DeVille 4.6L pcm
With the new PCM installed, we had a tow truck take me and the car to the local Generous Motors dealer for programming. Once programmed the engine starts and runs great! We put a few miles on it and checked for pending codes/monitors. Everything ran and passed...		 8
2001 Cadillac DeVille 4.6L a/c clutch
hello group jerry [...] hit the nail on the head...i had another deville come in and noticed voltage difference,,so i went ahead and replaced hi prssure switch,,,1 volt koeo,2 volts idling and 3 volts @1500 rpms...updated scan tool ,still didnt help,seems like ...		 5
1980 Chevrolet Step Van 5.7L Combo Brake Valve
Thanks to all that replied. Since this was a work van and the customer needed it ASAP, we took the valve apart and replaced an o-ring and all is good. Had good replies, but this year combo valve seems to be gone for good. I also could have put a universal adju...		 6
1997 Chevrolet Lumina 3.1L Hesitation
THANKS TO ALL WHO REPLIED. YOUR SUGGESTIONS WERE ALL GOOD DONOR PARTS WERE MAF TPS EGR. REMOVED O2 WITH NO CHANGE VISUALLY INSPECTED CAT AND WAS NORMAL. LET THIS ONE GO UNREPAIRED. CUSTOMER HAD $ LIMIT FOR DIAGNOSIS. I WOULD HAVE LOVED TO SWAP ECM. BUT T...		 13
1999 Chevrolet Tahoe 5.7L Misfire, MIL Lamp on
thanks for the many replies. most everybody was indicsting troubles with the valve train, weak springs or valves sticking in the guides. some other replies with cam sensor or distributor gears worn. i did not get any real good input on any troubles with specif... Trouble codes: p0306 (misfire cylinder 6).		 26
2004 Chevrolet TrailBlazer 4.2L AC Blower Operation
Of the 4 replies received, two hit it dead on (possible bad ignition switch). Thanks to all. Checked the ignition switch input and output voltage. Ignition feed to HVAC and EBCM (Same feed) had a 4-5 volt drop across the ignition switch when AC blower motor sw...		 4
2006 Chevrolet Express 4.8L Misfire
I think That My feeling were right all along. most of the responses were from people who do not know the engine, these engineS do not have FUEL PRESSURE regulators. some asked me to change and swap things i already did . i THINK lANEARD FROM TEXAS AND TODD f... Trouble codes: p0300 (Missfire-multiple).		 14
2006 Chevrolet Impala 3.5L No Start, Stall, MIL Lamp on
Thanks David from Arizona. Your experience has given us a direction to examine alittle more closely. We did pull that connection apart and even though it seemed normal we cleaned and re-connected that part of the circuit, making sure that the terminal is tig... Trouble codes: u0140 (BCM communication fault), u0073 (IPC communication fault).		 3
2002 GMC Envoy 4.2L fan clutch
i tested wiring according with alldata steps. all tested ok. swapped relay with another relay in relay box. cleared codes and test drove. no codes returned. many of you said youve had harness issues. so if it returns i will look closer on the harness. it is a ...		 9
2001 Pontiac Aztek 3.4L ign sw
THANKS SO MUCH FOR THE REPLIES.IATN IS AND ALWAYS BE A VALUABLE ASSET .THIS ONE ENDED UP BEING SOMETHING STUPID AND OVERLOOKED. ONE OF THE FIRST THINGS I HAD CHECKED EVEN BEFORE I PUT A SCANNER ON IT WAS THE NEUTRAL SAFETY SWITCH(FOR POWER THROUGH THE SWITCH)....		 3
2006 Pontiac Torrent 3.4L compressor
I finally have the air up and running on this Pontiac.I'd like to thank everbody who replied. Ron hit this problem on the head. He said to check the ambient temp sensor on the scanner. The sensor was way out of range. The sensor was damaged when the blend door...		 6
2000 Saturn LS1 2.2L ,
this one is fixed,once i remoned the water pump i saw that the water pump was in stalled wrong,causing damage to the ball shaft bearing,found metal meteral from the bearings.this car had 174000 miles on it so i replace the engine with a used engine with 46000 ...		 5
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