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(Also Available: All, Asian, Chrysler, European, Ford, GM.)
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Open Help Requests for GM
Help Request Answers
1993 Buick Park Avenue 3.8L Surge
The customer purchased this vehicle in the beginning of Sept. His wife took it on a 600 mile round trip, but broke down about 120 miles into the trip. She said it quit running. After a while it would start and run for short while and quit again. After about 3 ...		 View
1995 Buick Century 3.1L temp gauge
computer temp 225, fans come on, but coolant gauge reads overheating. changed both temp sensors & thermostat & still reads overheating.		 View
1998 Buick Regal 3.8L Poor Idle Quality, Misfire
Did a tune up and iv service and now i have a bad miss at 900-1000 rpms. Car drives and runs fine.. Changed plugs three times to see if would help..Injectors, wires, vac hoses are good and found no vac leaks.Replaced coils with test coils made no diff. I would...		 View
1982 Chevrolet Pickup 5.0L preignition w/loaded
thanks guys in advance for any information that you may have in this matter... the customer has a son that works at another auto repair shop. they have replaced the carburetor with a rochester quadrajet that appears to be functioning well enough at this time, ...		 View
1987 Chevrolet S10 Blazer 2.8L hydraulics
Replaced clutch master and slave bench bled system, and installed, was unable to get into gears, went from dorman parts to daiken parts to luk parts to no avail, all bled out of car and in the car, would not push clutch fork far enough to put into gear, instal...		 View
1994 Chevrolet S10 Pickup 4.3L bleeding
Installed new clutch master and slave cylinder, but the bleed procedure that came with them is crazy. There is no bleed screw on the slave. There is a small weep hole and a set screw. I suspect that when bleeding the clutch, fluid will squirt from the little h...		 View
1998 Chevrolet S10 Pickup 4.3L Cuts out
Hello I need some gm help. This is my sons truck and we have tried to get a lot of "known problems taken care of before he left for school 200 miles away. The truck shut off once 3 months ago after a 100 degree 1 hour trafic jam. Whent to pick up and it starte...		 View
1999 Chevrolet Cavalier 2.2L Transaxle
Hello Everyone, we have this Cavalier that the moment the car moves even an inch the low traction light comes for a couple of seconds then goes off until you stop again and then does the same thing.(Forward and Reverse) Now its not when the brake switch is act...		 View
2001 Chevrolet Blazer 4.3L Misfire, MIL Lamp on
this truck is crazy I don't feel misfire but it shows up on tech 2 miss on cyl 1,4 Number has the most misfire. I checked the dist gear for wear been replaced. I smoked checked intake system ok. The scope pattern looks good. I tried a plug wire. I hear guy say... Trouble codes: po335 (cranksensor), po300 (misfire cyl 1 and 4).		 View
2003 Chevrolet Silverado 6.6L transmission
sets codes po700 u1800 u2104 u2105 trans quits shiftining wiring harness has been checked also has new ecm,tcm original aftrmarkrt stero was installed killing bus installed factory radio still has problem also installed shift solenoids and trans range switch d...		 View
2003 Chevrolet Astro 4.3L Lifter
Hi Guys Thanks For Your Help , This 4.3 L Has a Lifter Noise at 1800-2300 RPM , Pulled Valve Cover I Could eliminate the noise by pushing slightly on # 4 Rocker , I Did not push hard enough to Colapse Lifter,intake was showing signs of Leak so might as well re...		 View
2003 Chevrolet Silverado 6.0L belt, tensioner
Hi All This should be straight up foward. customer says belt squeels when ac engauges, replaced belt. next day squeling again, replaced tensioner. this tensioner bounced all over when ac on, replaced tensioner again. three days later back again. replaced belt...		 View
2004 Chevrolet Avalanche 5.3L brake booster warnin
VEHICLE WAS BROUGHT IN WITH A SERVICE BRAKE BOOSTER WARNING IN INSTRUMENT DISPLAY. I CHECKED FOR CODES IN THE ABS AND THE IPC MODULE. NONE WERE FOUND. ACCORDING TO MY MITCHEL THE CODE WILL BE DISPLAYED IF IT RECEIVES A BAD SIGNAL FROM THE SUPPLEMENTAL BRAKE AS...		 View
2005 Chevrolet Malibu 3.5L MIL Lamp on
This car keeps setting codes for the EGR valve.It takes a while for the codes to set, but it is frustrating for both me and the customer. The dealer did the service bulletin for code P0404 on 1-2-07 @ 32636 miles which was to replace the Delco EGR valve with a... Trouble codes: P0404 (EGR position sensor error), P0405 (EGR position sensor low).		 View
2004 GMC Yukon 5.3L 4x4
my first help requist,(what a great resurce) here we go, .. 4x4 switch does not light up, 4x4 inop. no comunication w/modis scaner, tested power and grounds ok, all other systems comunicate ok w/pcm. no present fault codes found removed trtac fuse for 5 min. n...		 View
2006 GMC Sierra 6.6L Poor Fuel Economy
I have a 2006 GMC K2500 6.6L Diesel with the Allison automatic trans. This started out getting 18 mpg. and 14 mpg. towing a fifth wheel camper. Now my mileage has dropped to 10.5 mpg. towing. This is on long trips of several hundred miles at a time. I have che...		 View
1973 Pontiac GRAND AM 400CID programmer
Checked archives on exhibit A and nothing real productive other than this A/C unit is officially designated a Comfortron system. Automatic Temperature Control with a programmer fastened to side of air box underdash. Customers complaint is poor airflow. No high...		 View
1995 Pontiac Grand Am 2.3L Poor Idle Quality, Hesitation, Misfire, Poor Fuel Economy
customer wants this fixed for some ungodly reason...car acts like its running on 2 cyls...started with the coils and tower..tests showed bad coils...ran ok for a day or so...came back with the same prob...I warrented the coil tower and it ran fine for a day......		 View
2000 Pontiac Montana 3.4L power sliding door
I have looked through Alldata and cannt find a re Initilization procedure for the power sliding door on this Montana.can anyone point me in the right direction or email me the procedure.Thank you		 View
2000 Pontiac montana 3.4L Misfire
vehicle came in with engine light on dash & bad misfire on idle only of cyl # 6. we smoked engine & found leak from lower intake manifold gasket. we replaced with new gasket kit & replaced cyl # 6 injector. same problem. please help Trouble codes: po306 (cyl 6 misfire).		 View
2001 Saturn SL2 1.9L Electronic
hey fellow techs, this trans has erratic shifts and line pressures. driving with the modis the vehicle speed and speedo read fine , but the output speed sensor reads 0 when moving. my understanding is the vss is for both systems trans and speedo. question is w...		 View

Fixes & Summaries for GM
Fix/Summary Answers
1996 Cadillac DeVille 4.6L No Start
Well this vehicle it's out of my hair, i never had this car on my shop it was still on the costumer's house, but i learned few things about it, thanks to Juan [...], Ricardo [...], Pete [...], Victor [...], John [...], Alex [...], and John [...] ...		 8
1994 Chevrolet S10 Pickup 4.3L trans
What an SOB this job was. Finally got the trans out and back in again. It was like threading a needle. Thanks for all the great suggestions. I finally pulled the motor mount bolts and let the back of the motor drop a few inches. Thanks again!!!		 13
1994 Chevrolet S10 Pickup 4.3L clutch
Still putting this back together. It has been the job from hell. Once getting the trans out, found it was the clutch fork that has worn through the ball stud. On more day and its outta my shop!!!		 11
2004 Chevrolet TrailBlazer 4.2L Hesitation, MIL Lamp on
hi,thanking you all for the replys, the fix that solve the problem was replacing the catalic converter excessive back pressure again thanking you all. Trouble codes: p0410 (Seconary Air System).		 3
2004 GMC Sierra 5.3L heated seat
We replaced the drivers door module (switch) and it appears to have repaired the problems. Sorry for the delay as the customer takes this vehicle out of town and we finally installed the part today. Thanks for the help - I will add a comment to this fix if the...		 4
2004 GMC Sierra 5.3L transfer case
THANX FOR YOUR HELP GUYS. ALEX WAS RIGHT ON, I TOOK THE ENCODER MOTOR POSITION SENSOR OUT AND FOUND IT TO BE BROKEN. REPLACED THE SENSOR NOW THE TRUCK SHIFTS IN AND OUT OF FOUR WHEEL DRIVE WITH NO PROBLEM NO GRINDING. THANX AGAIN.		 3
1991 Pontiac Bonneville 3.8L No Start
thanks to you guys,when they unhooked remoult start they just un hooked a box left all the wires hooked up with fuses, so what i did was tear it all down to the way it was customer happy no more drain,i should of done this to start with insted of wasting all...		 4
2001 Pontiac Grand Prix 3.8L reverse
I would like to thank Alex, Charlie, and Matthew for their input. After replacing the reverse servo seal with no apparent success, I recommended that the customer let us install a rebuilt unit. At this point, the customer is driving it as it is. The economy...		 3
2002 Pontiac Firebird 3.8L Oil Pan
I thank everyone for the help they gave . Removing the low oil sensor first probly saved me from buying a new one. Don't try and get the pan out with out lowering the suspention. You will waste more time than just droping it and siding the pan straight out the...		 5
1999 Saturn SC1 1.9L Excessive Emissions, Poor Fuel Economy
AFTER FURTHER CHECKS FOUND OUT CAR CAME FROM AUCTION. WENT TO OHM INJECTORS AND COULD NOT REMOVE #4 INJECTOR CONNECTOR. TOOK A GOOD LOOK AT INJECTORS AND FOUND SOMEONE PUT WRONG INJECTOR IN EVEN THOUGH IT OHMED THE SAME AS OTHERS IT HAD TOO MUCH FLOW. REPLACED... Trouble codes: PO172 (system rich bank 1), PO304 (cylinder 4 misfire detected).		 2
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