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1994 Buick LeSabre 3.8L abs
hello everyone. i have an abs problem with this buick that i hope you can help me solve. the problem is that the abs light is on all the time. i have replaced the ebcm with no help.i went by alldatas trouble shooting of the pump motor and i can jumper pins 30 ...		 View
1995 Buick Regal 3.8L rear brakes
Vehicle came in for brake inspection before a trip. Rear rotors were badly rusted and when we checked, they were totally inoperative when applying brakes. Calipers looked like they had been replaced not too long ago. We tried bleeding the system but are gettin...		 View
1998 Buick Century 3.1L no speedometer
hello all vehicle has no speedo,and the indicator light for prndl does not lite when shifting gears,only the back ground lites. no codes in any module vss input is present at ecm,checked vehicle speed at ecm with tech 2 and all is ok but when checking at ipc r...		 View
1990 Cadillac Fleetwood 4.5L digital guages
this car came in with no cluster lights and the fuel data center and electronic climate control were not lighting up . I have repaired this problem many times so I consulted all data and checked the 16 volt wire coming out of bcm which powers up all the screen...		 View
1998 Cadillac Seville 4.6L MIL Lamp on, ABS lamps
ABS and TC lights on, NO MIL! Cannot command MIL on with scan tool. Codes 1560, 1599, 1602, 1604, 1611, 1641, 1644. Thanks for looking at this Caddy with me! ABS and TC lights come and go. Some loss of power. MIL does not come on at all. MIL will not self ch... Trouble codes: 1602 (loss of ABS serial data), 1641 (MIL cont. ckt.), 1560 (CC not in drve), 1644 (TP or torqued delivered), 1611 (loss of CVRTD data), 1604 (loss of IP data).		 View
2002 Cadillac Seville 4.6L No Start
This car was towed to us no start the other shop pulled the starter and it was fine...I hooked up the scanner and there is no comm..there is power at the connector but no comm..I checked all the fuses i could find..When you turn the key on all dash lights up n...		 View
1993 Chevrolet Pickup 6.5L No Start, Poor Idle Quality
This truck is starting hard all the time when cold and intermittently after warmed up. Customer stated that he had to jump the glow plug relay because sometimes the glow plug light wouldn't come on. It takes about 10 minutes of cranking and waiting in order to...		 View
1994 Chevrolet S10 Pickup 2.2L no power
Customer said car has been running bad for about 1 year. Test drive shows poor power.Customer also stated he heard a rattling noise in exhaust that eventually stopped. Vehicle acts like cat convertor clogged. Tested vacumn at 2000 RPM for 2 minutes 20 in. No s... Trouble codes: 44 (Lean exhaust).		 View
1994 Chevrolet Camaro 3.4L Excessive Emissions
Car has been e-tested 12 times always fails on NOx tried everything. more money spent then car is worth. It must pass due to re-sale regulations. Someone help please. Can't even insure it to burn it.		 View
1997 Chevrolet S10 Pickup 2.2L detonation
this is my s-10 that had a blown engine i swapped in a shortblock from a 99 cavalier but now it spark knocks/detonates on accel from what i have found out the cam is a little different the dish in the piston as little shallower and the notch on the crank for t...		 View
2000 Chevrolet Camaro 3.8L Excessive Emissions, Poor Idle Quality, Hesitation, Surge, Cuts out, Misfire, MIL Lamp on
Thanx in advance. 2000 camaro with a K vin 3.8 and 4spd auto. This car came in to shop with some parts already replaced. The 1/4 coil and ign. wires, as well as plugs. 7 times out of 10 the car will start and idle perfectly. When the throttle is snapped it ... Trouble codes: PO300 (random misfire).		 View
2001 Chevrolet Express 4.3L No Start
Hello GM Techs, I have a van that got towed in for crank no start. Found spark, fuel pressure from pump, but no injector pulse. Also tried to check codes and data with Snap-on Modis and no communication at all. Tried other scan tools and same thing. I checked ...		 View
2001 Chevrolet Silverado 4.3L Mechanical
hi i have a 01 silverado after trucks sits all night the lifters make noise after truck warms up they quit down oil preasure seem good 60psi i found a tsb about the o ring at the pick up tube im wondering if anyone has replaced the o ring for that problem than...		 View
2002 Chevrolet Impala 3.4L anti-tehft
HELP! P2960 passlock cylinder data incorrect.I replaced the passlock sensor a year ago customer returned intermittent no start car drove in replaced passed lock sensor under warranty.Followed the procedure for manual reprogram just like i did the last time the...		 View
2002 Chevrolet TrailBlazer 4.2L Unknown
Hello, We have a Trailblazer that was towed in. Here is the customer's story: He drove home and parked in the driveway. Went to pull out the next morning and nothing happened. When he went to put it back into park to shut it off, he heard a grinding noise. He ...		 View
2004 Chevrolet TrailBlazer 4.2L 4hi/4low
Hi Group. Just wondering if anyone has come accross this before. Road tested in snow-covered back lot. Vehicle works seemingly ok in AWD and 2wd. Problem occurs when you select 4HI or 4LOW. Sounds from underneath tell me that transfer case is engaging and pow...		 View
2005 Chevrolet Malibu 2.2L Hesitation, Misfire, MIL Lamp on
Hello fellow techs, I have a 2005 Chevy Malibu here that has a P0106b and a very erratic misfire. It will misfire on cylinders 2 and 3, then stop and misfire on cylinders 1 and 4. then it will jump back and forth between the four cylinders. Alldata flow chart ... Trouble codes: P0106B (manifold absolute pressure sensor performance).		 View
2003 GMC Sierra 5.3L front end.
truck came in for new tires,(305/70R16 Destination AT)inspected front end, found bad LF upper control arm bushings, installed new bushings and aligned vehicle to factory specs. truck does have 6 in. suspension lift, customer stated he bought truck new already ...		 View
2003 GMC Yukon XL 5.3L MIL Lamp on
truck came in with mil on. code po125 stored. replaced t-stat cleared code and all was fine for a few months. came in for lof and noticed mil back on. same code. cust. said it just came back on. dealer told us to replace t-stat housing, so we did. came back wi... Trouble codes: po125 (insufficient coolant temp).		 View
2005 GMC Yukon 6.0L MIL Lamp on
Hi guys and gals, this yukon will not except fuel at a normal rate. Takes about 20 minutes to fill the tank. Code PO446 is active. My Alldata is not giving me alot of infomation on this. I removed the solenoid for the rear of the tank wich i believe is the ven... Trouble codes: po446 (Evaporative Emission System Vent Control Circuit).		 View
1996 Oldsmobile Ninety-Eight 3.8L MIL Lamp on
Hi Folks, I replaced this 3.8 engine with a used engine from another model Olds. The junk yard wasn't sure of the year or model. The code that turns on the MIL sets "if an improper voltage level is detected on the output driver module B output 5" This is the E... Trouble codes: 1655 (EVAP solenoid control circuit does not turn on MIL), 1654 (AC relay control circuit turns on MIL after 2nd start).		 View
1999 Oldsmobile Alero 3.4L code#p0341
"ANY" ideas on this one would be very much appreciated, as I said in the related history, I have done extensive testing, including tapping the CMP sensor (the one I fitted was a "blue streak" brand, usually pretty good) also tapping the computer, checking conn... Trouble codes: P0341 (cmp cam position sesorcircuit failureproblem).		 View
1997 Saturn SL2 1.9L MIL Lamp on, PO172
Done everything we can think of. Still running rich, but runs and drives perfectly. Freeze frame info: ST fuel trim: -7.0, LT fuel trim: -21.9, MAP 13.6 hg Rpm 778. Closed loop. Will only set code when foot on brake in drive. Will consistently reset code after... Trouble codes: PO172 (Fuel system rich bank 1).		 View
2000 Saturn LS2 3.0L steering wheel shakes violently and rduuced ower i
picked up this car for my college student daughter after she decided to leave her 1994 acclaim in low and hit the interstate --the trooper made it 3 miles before she blew the 2.5 with 160 rounds, anyway this saturn is gutsy thing so i hit the interstate and th...		 View

Fixes & Summaries for GM
Fix/Summary Answers
2003 Cadillac CTS 3.2L no heat in cabin / smell inside of car
Thanks to all who helped with this problem. This vehicle had several problems. First, the retaining ears for the thermostat was broke on one side. Second it had a bad solnoid on the heater control valve on the right top of radiator causing no heat in cabin are...		 9
1976 Chevrolet Camaro 5.7L oil pressure
Wow, thanks for the great responses. We had checked the cup plug underneath the rear main by measuring from the rear pressure port. It was OK. Also, the front plugs were already converted to screw in style. All new camshaft bearings and the student was pret...		 37
1993 Chevrolet Suburban 5.7L MIL Lamp on, high idel
sorry it took so long,i forgot to close this. i ran a new wire from tps signal to ecm and noticed it was a 10 year old napa reman to i installed a standard reman ecm,all is good and customer even believe's the mileage and performance have improved.thank's to a... Trouble codes: 22 (tps low voltage).		 17
1993 Chevrolet Lumina 3.1L Stall, MIL Lamp on
Alright guys, thanks for all your help. Sometimes it's the easy things that make life hard. Here is what was going on. On this particular car my students were using the Snap on 2500 because it was an older vehicle. I didn't try the Solus or Modis on it to ...		 14
1993 Chevrolet S10 Pickup 4.3L Excessive Emissions, Poor Idle Quality, Hesitation
This vehicle is finally fixed. I removed the plugs and they were fouled, probably from me trying to start it out of time. I replaced the plugs and reset the distributor. And all is well. Thanks for all the great help.		 16
1996 Chevrolet Tahoe 5.7L transfercase
Was just able to get back to this truck last night.We pulled the transfer case apart and found the syncro had broken apart.Two of the three locks had fallen out and the the round spring that holds them in was twisted up and stuck near the chain.We are replacin...		 13
1997 Chevrolet Pickup 6.5L abs
Thanks to all the guys who responded - everyone was suggesting speed sensor issue. I pulled the sensors and cleaned up a little rust and sure enough - the problem disappeared. I obviuosly had an amplitude problem which I did not pickup with the labscope. Also ...		 9
1998 Chevrolet Pickup 4.3L Mechanical
Thanks to all that helped me. When I removed the intake and valve covers I found the intake gaskets blown at the water jackets. Installed new lifters, intake gaskets, and valve cover gaskets. Also, flushed engine to remove the oil that had mixed with the co...		 23
2000 Chevrolet Blazer 4.3L drive belt
Well,this beast is off and running again.Turns out adjusting the position of the power steering pulley solved all of our problems.All of us here learned a lesson.Never ignore even the smallest of details.I would like to again thank all the techs that took time...		 24
1994 GMC Suburban 5.7L Excessive Emissions, Cuts out
Turned out to be the dist pickup signal weak at low speed. thus causing the stall hard wheel crank at idle. thanks to Stan from Minnesota for the push in the right direction. the closed loop situation was the stat stuck opne, which was checked by other tech wi...		 8
1997 GMC Sonoma 4.3L Red Brake Warning Light stays on
To begin I would like to thank every one who replied to my request. I would also like to apologize for not posting until now; but the customer never brought the truck back. This is his work truck and he was in a hurry that day looking for a quick fix and didn'...		 4
2003 GMC Yukon 6.0L Poor Idle Quality, Hesitation, Cuts out, MIL Lamp on
Thanks to those that responded, all of the grounds were tested and cleaned, the lab scope images that I had gotten were the result of the throttle body motor and the current that was required to open / close it. I replaced the throttle body assembly, and all i... Trouble codes: P1516 (Elec. Throttle Mod. VS).		 3
2003 GMC Envoy 4.2L electrical
FINALLY! Problem with draw turned out to be a faulty "PDM" or passengers door control module that kept other modules (connected by it's serial data link) "awake" due to internal fault when cold. Same 2800 miliamp draw was induced when new module was installed...		 16
2000 Oldsmobile Silhouette 3.4L Surge
After many hours of checking everything, we come up empty handed. We tried: New oxygen sensors, new TPS sensor, new MAF sensor, a new fuel filter; we blocked off the EGR Valve, we ran a digital fuel pressure tester, we cleaned the throttle body and the fuel ... Trouble codes: P0131 (HO2 1-1 voltage too low), P0137 (HO2 1-2 voltage too low).		 13
1999 Pontiac Grand Am 3.4L Fuel Gauge,Odometer
When this vehicle came in for an engine R&R,we removed the computer to test another vehicle(same numbers).The computers never got switched back.Under tech2 self programmimg the vin didnt match the car.Reprogrammed the PCM with the correct vin took care of both...		 6
2001 Pontiac Grand Am 2.4L Body Computer
Thanks to Joe and David for replying to my unusual post. Gentlemen this is one for the books! I learned something, I'm just not sure what that is. I took the part numbers from the old bcm,the new bcm, along with the vin and made a trip to the dealer. The p...		 2
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