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Open Help Requests for GM
Help Request Answers
1997 Buick Century 3.1L Hesitation, Surge, Poor Fuel Economy
loss of power on mid-range accell. the car ran fine with the maf reading 0g/s. i am looking for other possibilities. on light accell and heavy accell everything seems normal. noticed car has a hard time getting over 70 mph		 View
2000 Buick Century 3.1L ac
greetings to all,i have a buick century here that has dual climate control system,the drivers side gets nice and cold but the passenger side stays warm.i evacuated and recharged ac with correct amount of refridgegerant and it does the same thing.i went to the ...		 View
2008 Buick Enclave 3.6L sir
Hello everyone, I've got a tough one here. The vehicle is a 2008 buick enclave. It came to me from a body shop after a collision repair.The sir light was on the dash. The air bags deployed,so I replaced the sdm and programed it through tis2web with a tech 2 sc...		 View
2002 Cadillac DeVille 4.6L converter
ATTN cadillac guys. Vibration. The perverbial ever since came up. Now the vehicle has a vibration while driving and the converter is locked. The vibration seems to be around 42-48 MPH and around 1300-1500 RPM. We can get a vabration to occure in neutral in par...		 View
1988 Chevrolet Pickup 4.3L Poor Idle Quality, Hesitation, Cuts out
vehicle was towed in customer complained of a backfire and the vehicle would not run after that.i checked for spark and there was none,replaced the ignition module and coil and the engine started.i test drove and the truck would not go over 3o mph and would no...		 View
1993 Chevrolet Hi-Cube 5.7L engine
After engine replacement the owner came back with the complaint that the truck is using approximately a quart of oil every 1000 miles or so. At first we contributed it to break-in. Came in at approximately 8000 miles and spoke with vendor. They requested we re...		 View
1995 Chevrolet Caprice 5.7L poping sound
Hi Guys.Have a problem with this impala ss.I runs good but when you give it gas hard it popes out of the intake,but when you give it gas not too fast it is fine.It has a new cap and rotor,wires,and plugs look like new.at ilde the tps is .66,the iac is 0,the ai...		 View
1998 Chevrolet Tahoe 5.7L Surge, lack of power
this is the second time this vehicle has been back for this problem. customer states that after the vehicle has warmed up that it starts surging and has a lack of power (states that it can't get out of it's own way). the first time we had it, it would get warm...		 View
1998 Chevrolet Blazer 4.3L Air Mix Actuator
Hi folks, this truck came in with the AC blowing hot air only. The control module says B0408 Temperature Control #1 (Main/Front) Circuit Malfunction and B0416 Temp control circuit high. With the actuator DISCONNECTED, I have about 4.5V on circuit 733 (the ligh...		 View
2000 Chevrolet Monte Carlo 3.4L 1-2 shift
I aquired this car from one of my customers.It needed an intake manifold gasket,cooling fan assy.& a radiator. It was more money than he was willing to spend so he sold the car to me since I have a teenager that will be needing a car in the near future. He men...		 View
2001 Chevrolet Tracker 2.0L Cylinder Head
I just want to start by thanking all who respond in advance. The customer brought this vehicle in and complained of coolant getting into the spark plug tubes. I first checked all of the tubes and found water contamination in all of the tubes but cylinder 3 did...		 View
2002 Chevrolet Camaro 5.7L Misfire
This vehicle came in with a check engine light on, and I found two codes. PO300 random misfire and PO420 catalyst efficiency bank 1. I found and repaired the vacuum leak on the pcv harness. I also found a dirty MAF sensor (K&N), I cleaned the sensing elements.... Trouble codes: PO420 (Catalyst Efficiency Bank 1).		 View
2002 Chevrolet Impala 3.4L radio lighting
Radio display cuts out when interior light dimmer is turned to bright, flickers bright and dim when turning dimmer knob. Only the display cuts out, the lights behind the number keys and buttons remain constant as do the instrument display. Vehicle recently had...		 View
2002 Chevrolet Silverado 4.8L Poor Idle Quality
pickup came in with check engine light and rough running. had a random missfire code and #6 cylinder didn't seem to want to balance. spark plugs were replaced and motorvac done. customer drove for a week and came back saying it still did not idle well and chec...		 View
2002 Chevrolet Malibu 3.1L ignition switch
I had to drill out the tumbler on this Malibu, as the key all of the sudden would not turn. I got a tumbler, with 2 keys from Carquest. After installing the new tumbler, the car started once and died; now no start. The red "theft system" light blinks on the da...		 View
2003 Chevrolet S10 Pickup 4.3L Poor Idle Quality, Hesitation, Misfire
Install new gasket on intake and can not get distirbutor timing set it has a poor idle... and no power lined up timing marks correctly...the books and manuals say no timing adjustments... their is no codes no vaccum leaks me just stumped... any chevy fans than...		 View
2003 Chevrolet Express 6.0L Misfire, MIL Lamp on
Hey Gm fans got a good one here, this 2003 g-van has a miss tech2 says number 6 cyl, fuel pressure ok, we have swaped ignition coils, fuel injectors, checked fuel rail for debries, none replaced upper intake gaskets, have spark and injector pulse at cyl 6 vacu... Trouble codes: p0300 (misfire).		 View
2004 GMC Yukon 6.0L Traction control
Had codes COO35 & COO40. check out rear wheel speed sensors res good bias voltage good do not loose any signal on the scantool. but at a certain speed at a certian place the traction light blinks, and the truckgo into reduced engine power for about 4 sec then ...		 View
2004 GMC Envoy XL 4.2L Misfire, MIL Lamp on
Vehicle was driven in, cutting off ses light was on and flashing also reduced power light was on. Check dtc found po302 cyl 2 misfire, R&R coil and plug, spark plug was soaked with fuel, used a spark tester on coil no spark. Removed cylinder 3 coil and tested ... Trouble codes: po302 (misfire cylinder number 2).		 View
1991 Oldsmobile Ninety-Eight 3.8L MIL Lamp on
All circuits test good with the exception of the AB circuit at the Cam sensor. It is only reading 4.99 volts. The BC side is reading correctly at 11.55 volts. Found wiring harness rubbed thru on a stud, repaired harness. Also found that the trigger for the Cam... Trouble codes: 41 (Cam sensor circuit).		 View
1995 Oldsmobile Cutlass Ciera 3.1L Poor Idle Quality, Stall, MIL Lamp on
This Olds runs great, but it cuts out and dies in gear at idle. Code p0341 for cam shaft sensor. Lab scope shows erratic pattern coming out of sensor. Replaced sensor with no change. I doubt we have an ecm issue because it is probably seeing the same thing my ... Trouble codes: P0341 (Cam position sensor).		 View
1997 Pontiac Bonneville 3.8L Starting
Ok this is my first session getting on here. I need HELP. This vehicle is having problem with security light coming on and vehicle not starting intermitant. This problem has been happening for a couple of years know. Firts thing i did was bypass lock cylinder ...		 View
1999 Pontiac Grand Am 3.4L ecm
Hello fellow techs I have a problem with this vechicle with U codes U1000 loss of class 2 serial com and U1016 lost comm with ecm. This is very intermedate have seen problem before always has been ingition switch. After replacing switch still does the same pro...		 View

Fixes & Summaries for GM
Fix/Summary Answers
1997 Buick LeSabre 3.8L convertor
the replys that i received were all going in the same direction. everyone was in the opionion that the trans needed to be gone through but the customer opted out.bruce from ontario was one of the replys that i felt was right on target. i appreciate everyones h...		 19
2001 Cadillac Seville 4.6L Cooling Systems
thanks everyone for responding,i have in the past put the pellets in cooling system,let vehicle sit overnight with cooling press tester hooked up and the next morning when i cranked it over no coolant came out of any cylinder.it is probable that a head bolt ma...		 17
1989 Chevrolet Corsica 2.0L Stall
IATN IS A GREAT SITE, THANK YOU ALL FOR ALL YOUR HELP. THANKS ESPECIALLY TO JOHN, KEVIN, BOB, AND RAY, I WAS LEANING TOWARDS THE INJECTOR BUT I HATE TO THROW PARTS AT A VEHICLE NO MATTER WHAT THE CIRCUMSTANCES. I DID CHECK THE GROUNDS AND THE PCM FOR CORROSION...		 12
1992 Chevrolet Corvette 5.7L ars/abs
Thank-you all who responded to my help request. All info. that was given made me go back over and ck on all that was done. The end result was that the engine coolant tempature sensor for the E.C.M. that is in the front of thewater pump was cracked and had fall...		 4
2003 Chevrolet Silverado 5.3L Hesitation, Misfire, MIL Lamp on
well, this one is out. we smoked the intake again and found no leaks. I rescoped the 02s and all looked well. finally i put the scope on the maf. Found the maf to be bad. replaced and all is well. thanks for all the great advice. sorry it took so long to clos... Trouble codes: po420 (catalyst efficiency below threshold b1).		 10
2003 Chevrolet Cavalier 2.2L timing chain
I had an insert installed in the cyl. head for the stripped threads, ordered a new bolt from G.M., and installed the chain kit. lined up timing marks with new guides and tensioner, also cleaned all debris (guides and bolt) under the oil pickup tube in the oil ...		 3
2003 Chevrolet Silverado 5.3L Rear Axle
You folks are great! Thanks for all of the responces. The vast majority of them recommended greasing the splines on the end of the rear driveshaft that fits into the transfer case. I did this and the problem went away for one day. Several folks recommend...		 16
2004 Chevrolet Venture 3.4L High idle condition
Well it's fixed and here's the details. The 5v ref circuit from the pcm to the tp egr and the map and the low ref signal on the same circuit back to the pcm were rewired from the sensors back to the pcm. We found the tp sensor glitching from 0 to 1% going bac...		 11
1995 GMC WT-500 7.1L Brake light switch
Gentlemen thanks very much for the replies. We finally received the proper information on this vehicle after the third try. What I found was the brake light relay having a loose internal contact. Relay replaced brake lights work!!! Yes!. Thanks again to e...		 4
2004 GMC Envoy XL 4.2L trailer wire
Thanks to all who responded. The wires were in left side taped to harness. Had to remove lower trim panel and hvac floor duct for dr side to see/ acess them.		 6
2005 Pontiac GTO 6.0L starting
Well the general concensus is that I shouldn't tamper with the emission system because there are fines associated with this. Several people "enlightened" me about this. As for the original reason that I posted the question wasn't even covered. I found out that...		 6
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