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1991 Buick Regal 3.8L Poor Idle Quality, Hesitation, Stall
this car came to my shop and the problem is to high at idle,(3000 rpm) actually i put another iac valve and i cleaned the throtle body, y check the pcv valve there isnt any dtc i was looking for any vacuum linkage but i didnt find anything. ill apreciate your ...		 View
2000 Buick Park Avenue 3.8L LH tail and parking lamps stay on
A very good customer of ours brought her car in last week claiming only the left front parking lamps and the left rear tail lamps stay on occasionally after the car is shut off (happened twice within about a week). We could not duplicate the problem that day. ...		 View
1960 Cadillac SEVILLE 5.0L Mechanical
hey cadillac tech's sorry about the no vin & the incorrect engine size. we need to rebuild the engine on this old girl & i need some information on suppliers who would stock parts for old cadillacs. thanks again andrew		 View
1997 Chevrolet Cavalier 2.2L Mechanical
hi every one i have this 97 cavalier with a valve noise it sounds a little louder than a lifter before we take it apart has enyone ran into bad valve guides in a 2.2 or lifters thanks in advance jeff		 View
1998 Chevrolet S10 Pickup 4.3L Poor Fuel Economy
i just got this truck havnt had much time to mess with it so i dont know much about it the truck is only getting about 13-15 miles per gallon on the highway just wanted to know if any one has had this problem before if it is a problem i have replaced the lower...		 View
1999 Chevrolet Pickup 5.7L power steering
Customers complaint is no power steering when turning left at slow speeds, if cylce brakes (hydroboost system) power steering will come back, if it was not hydroboost I would suspect valve problem in gear box, I dont have many heavy truck customers so it is a ...		 View
1999 Chevrolet Express 7.4L Poor Idle Quality
Car Ilde drops down to 300 rpm runs rough and feels like misfires, give it gas and doesnt want to go anywhere checked fuel filter and was very dirty replaced then was told it could be fuel pump psi was at 45 to 47psi replaced fuel pump check crank sensor and m...		 View
1999 Chevrolet Malibu 2.4L cluster - turn signals - a/c - starting
Hello fellow techs - I have here a malibu with a no start - no turns - no a/c - and no cluster gauges or lamps.Car has theft codes in PCM & BCM. live data from BCM with snap-on modis shows this - ign 0 output- inactive - passlock data invalid- phase lock loop ...		 View
2002 Chevrolet TrailBlazer 4.2L window switches
Howdy Everbody, College boy hooked the jumper cables up backwards and blew the 125 amp body fuse. I replaced the fuse and now everything works except the windows, I get battery voltage on the up/down signal wires and the lock out wire at the switches but no wo...		 View
2002 Chevrolet C3500 HD 8.1L brakes
We had found that the left rear wheel speed sensor was melted. At that time we found the right front and left rear wheels were significanatly hotter (about 100 degrees) than the other two. After replacing it (left rear speed sensor) we took it for a test drive...		 View
2003 Chevrolet Express 6.0L Misfire
hi every one, truck came in with engine misfire, run scanner and found code po300 random misfire, #6 misfire, truck never had tune-up, so replace spark plugs, wires, gas and air filter, after tune-up. started van and runs great, test drove and came back to sho... Trouble codes: PO300 (random misfire).		 View
2004 Chevrolet Cavalier 2.2L abs
It feels as if the porpotioning valve is stuck. The rear brakes feel like they are doing the majority of the stopping. When braking the car squats rather than dives. It has worn out the rear brakes prematurely. I am getting on history code, c1214. Any response...		 View
2005 Chevrolet Suburban 5.3L transfer case
transfer case pops out 2WD into neutral at stop or shifting in between reverse & drive. Works fine in 4WD. no codes present. Have seen post about encoder motor sensor but can't find into in alldata about how to service sensor. anyone else have this trouble bef...		 View
2006 Chevrolet Express 5.3L MIL Lamp on
remove injector rail found alot of rust type material in the rail and in the top of each injector installed new injector and cleaned the rail problem gone for now Does anyone know if their is a filter that can be put in line to help filter the gas Trouble codes: p0307 (cylinder missfire 7 cylinder).		 View
1987 Oldsmobile Cutlass Ciera 2.8L Cuts out, Stall
ECM or PROM??? While watching live data and having VOM hook to MAP signal return I can see that ECM is not 'reading' correct voltage along with associated symptoms.(off idle hesitation,stalling etc. VOM Does display correct voltage based on throttle but PCM li... Trouble codes: 34 (low map).		 View
1998 Oldsmobile Silhouette 3.4L transaxle range switch
van came in with a complaint of sputtering and stalling after driving short distances. scanner resulted in code p0706-transaxle range switch performance. using snap-on tech. (mitchell) ran all diagnostic procedures. all seemed ok. but tried new TRS(nuetral saf...		 View
1999 Oldsmobile Intrigue 3.5L engine
Hey guys, Customer states that has a long crank intermittent. Has codes P0335 & P0340. Both sensors were replaced. Leaning towards a ignition switch just because i have seen them do weird things before. Hoping someone had similar problem. Thanks Mike		 View
2001 Oldsmobile Silhouette 3.4L cooling fans temp gauge
This van has cooling fans that run all of the time when engine is running. Temp gauge not working. Trouble codes are po 128 engine below operating temp & inst cluster code b1440 power mode master input circuit miss match. When code is cleared for inst. cluster...		 View
2002 Oldsmobile Alero 3.4L No Start
Cranks o.k, no injector pulse, cold. Has spark. IS NOT AN ANTI-THEFT ISSUE !!! All injectors have voltage but are not grounded by the pcm. Pulse injectors with the scan tool and the car will then start and stay running. Once the car has run for about 5 minutes...		 View
2002 Oldsmobile Alero 3.4L No Start, INTERMITENT
vechile sits outside in sun for a period of time. the complaint is that it wont start and the door locks keep on unlocking and locking. when it stops the vechile will start. there are 5 codes due to loss of communication. plus in shop it will not start then tu... Trouble codes: U1000 (loss of communication), U1128 (loss of irc), U1255 (loss of class 2 commun.), C1298 (pcm class 2 serial data link fault), P1585 (cc inhibitcc lamp control circuit).		 View
1990 Pontiac 6000 3.1L Surge
after it warms up in gear at times after setting at a light etc. for a while it will surge up and down and run very rich. smoke coming out the tail pipe. wh tryed disconnecting the map. no change the o2 no change, the ecm has been replaced. no change. the grou...		 View
1992 Pontiac Firebird 3.1L Poor Idle Quality, FLUTTER
Firebird came in with a flutter at idle after warm up,this low milage car had all the original tune up parts so we replaced plugs wire cap rotor pcv valve fuel filter and found the distibutor was covered in rust so now its new also replaced the o2 sensor. no c...		 View
1995 Saturn SL1 1.9L MIL Lamp on
Customer brought in for MIL on. Found DTC 11,no other codes in PCM and no codes found in TCM. Checked TCM for codes with scan tool and by shorting out ALDL to get overheat light flash, no codes found. On test drive found coolant to temp to run low, checked Ide... Trouble codes: 11 (PCMTCM Codes Stored).		 View
1996 Saturn SL2 1.9L belt tensioner
hello i sure hope some one knows how to cure this one we installed a new belt tensioner and belt since then when the ac is on and car is idn drive the belt tensioner makes a hard clicking noise we installed two after market tensioners and a new belt the ps and...		 View

Fixes & Summaries for GM
Fix/Summary Answers
1995 Buick Regal 3.8L Surge, Stall, MIL Lamp on
I'm still waitng for a reman ecm that I ordered about 2 weeks ago. Imagine that.I will repost this with any updates when the ecm arrives. thanks to all who replied the general thought was a bad ecm we will see. Trouble codes: p0113 (iat high), p0118 (ect high), p0137 (o2 no.2 low), p0140 (o2 no.2 high), p0341 (cam and crank error), p0502 (vss no signal).		 10
1992 Cadillac DeVille 4.9L engine
thank everyone for all their help. I utilized the responses and check as much of the passkey as I could. it was receiving a good signal from the key but only sending a 30 hz signal to the pcm. I was informed it needs to be a 60 hz signal. at this point it...		 9
1999 Chevrolet Silverado 5.3L seat tracks
So far it looks like the only way to resolve this is to buy new seat risers from GM at about $800 each, Now my wifes 98 Blazer is starting to do this,,,Thanks GM Engineers!!! How brilliant of you to figure a way to turn a place to rest our butts into a techinc...		 5
2002 Chevrolet Camaro 5.7L Misfire
Thanks to everyone who gave me great advice. It is very helpful to have other techs to workout these problem vehicles. The fix for this car was factory warranty on the converters. The dealer replaced both units and all is well. Thanks again for all the help.... Trouble codes: PO420 (Catalyst Efficiency Bank 1).		 17
2004 Chevrolet Cavalier 2.2L ignition lock cylinder
thanks for your help if i didnt get a second opinion from you guys i would have had a steering column out today tapping with a hammer and turning key did the trick we replaced lock cylinder and key and everything works good thanks for the time saving tip phil		 7
1994 Geo Tracker 1.6L performance
My thanks to all nine of you who replied to my question. I'm not much of a welder unless it's a last resort so I got a new key and filled the hogged out area in the crank with JB Weld;it went together well and now it runs like a bear! 		9
1997 Pontiac Bonneville 3.8L Starting
Ok the problem has finally happened to me the security light came on and vehicle would not crank over. What i found is the resistance is fine coming from resistor i bypassed from pass lock sensor. But when i turn the key on resistance is lost. Cut purple/white...		 9
1999 Pontiac Grand Am 3.4L ecm
Thanks for the help. The vechile came from a used car lot upon furthur investagtion the computor spit out 2 more codes P601 EEPROM Flash Error and P1626 Loss of serial commucation with vechile theft deterent system. When I went to order a new computor found t...		 3
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