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1963 Buick Riviera 400CID Engine
We had just recently replaced the transmission in this vehicle, ever since the car has had a bad vibration. The vibration can be felt just off idle up to about 2000 rpm. The car does not need to be moving to feel the vibration. The vibration is not felt at hig...		 View
1991 Buick LeSabre 3.8L egr
I have gone threw the basic GM tests, and it tells me (cloged EGR passage, or replace EGR) I replaced it once, came back the next week, tested, replaced it agin thinking bad part, came back 3 days later.. any ideas? i checked passages and the all seem to be cl...		 View
2004 Buick Park Avenue 3.8L rear suspension
this car drives and rides remarkebly well on smooth roads. when you encounter bumps in the road or a ridge were the concrete and pavement meet at the edge of a bridge you get rear bump steer for a couple of seconds and then the car returns to normal. I was onl...		 View
1996 Cadillac Fleetwood 5.7L Heater
The heater will output some warm air if you let it sit and idle, but as soon as you start driving it gets cold. Heater outlet hose is cold. Water pump,thermostat and heater core have been replaced. Heater hoses were temporarily bypassed (car has a restrictor i...		 View
1997 Cadillac Catera 3.0L Poor Idle Quality, Misfire, MIL Lamp on
Hey guys thanks in advanc3 for any info offered on this repair... first of all I would like to know if anyone has any info on the timing belt besides what i have on mitchell or autodata. The mitchell asks for a special tool and I cant get it here in Mexico. So... Trouble codes: p0300 (multiple cylinder misfire), p0301 (cylinder 1 misfire), p0303 (cylinder 3 misfire), p0305 (cylinder 5 misfire).		 View
1990 Chevrolet Corvette 5.7L Misfire
Hello all, I have a 1990 corvette that has 3 dead cylinders at all times, #5,6,7 CYLINDERS. Have scope tested igntion and even replaced all igniton components except internal distributor parts, have tested compression-good, have scope tested injector pattern...		 View
1994 Chevrolet Pickup 5.7L Excessive Emissions, Poor Idle Quality
Good evening GM techs.I have an old pickup here that is driving me crazy.I start it cold and the tailpipes look like chimneys,black coal.as it warms up it goes into closed loop and starts to idle marginally better but not much.Coolant temp is right on spec.the...		 View
1994 Chevrolet Camaro 5.7L Starting
towed camaro in for a no start. someone had take the radio out plus the theft deterrent modual [tdm] and cut the pigtail to it. went to the sal. yard pick up pigtail and used tdm. towed car to dealer to have new key made for the tdm. starter still will no enga...		 View
1994 Chevrolet Pickup 6.5L No Start
Any help would be greatly appreciated. This truck came in for a battery/starter problem it ran fine. The connections at the batteries were severely corroded, simple fix, cleaned up and it now cranks great. But when it started the S.E.S. light came on and the e... Trouble codes: 35.		 View
1996 Chevrolet Express 5.7L rear shoes
Hey guys, customer has been coming to us for about 5 years. Always had concern that rear brakes don't have enough stopping power. Recent snow he was in an accident, now wants us to try to resolve issue. All brakes are new AC/DELCO. Found a tech bulletin (99-05...		 View
1996 Chevrolet Pickup 5.7L Cuts out, Misfire, backfire
After warm up it looses all power. It looses power like gradually but quickly as if it were running out of fuel.It also pops through the throttle chamber.I can ease up off the throttle and it catches on enough to get somewhere.Engine straightens out if I riche...		 View
1998 Chevrolet Monte Carlo 3.8L Master Cylinder
This car has a soft pedal and the master cylinder needs replaced. The ABS motor pack bolts directly to the master cylinder and both master and abs have to be removed as one unit then seperated to replace the master. The repair proceedure says that you need to ...		 View
1999 Chevrolet Pickup 5.7L No Start
Replaced intake gasket reassy no spark. performed flow chart per Alldata replaced Ign Control Module. still no spark. Ignition voltage fine, Do get spark when you turn key on and off at times. Checked all connetions. Getting Voltage from crank sensor. Scann... Trouble codes: 1351 (Ignition Coil Control CIrcuit High Voltage).		 View
1999 Chevrolet Astro 4.3L No Start
Towed in and starts but stalls. Found No power on red/white wire at passlock sensor at ignition switch. Power from fuses and ground OK TO the passlock module but still nothing on red/white wire (12v ref). Unfortunately this 99 is different from a 98 and 2000. ... Trouble codes: p1626 (loss of serial communication with VTD), u1192 (loss of EVOVTD passlock communication).		 View
2001 Chevrolet Silverado 4.3L Misfire, MIL Lamp on
hello techs, i have a 01 chevy c1500 that came in with a no start. replace plugs, wires cap and rotor, still have a #3 misfire at idle. checked and found leaking injector, so i converted the cpi unit to a mpi unit. still missing. am i overlooking something o... Trouble codes: P0300 (random cylinder misfire).		 View
2001 Chevrolet Suburban 5.3L p/s
thanks in advance. our shop has this truck that as no power steering assist while on a incline(driveway).pump pressure is1200-1300 psiwhen trying to turn steering.the steering will turn to left or right but as if the eng. was off.front end is good.seems like a...		 View
2002 Chevrolet TrailBlazer 4.2L MIL Lamp on
Grettings to all,this trailblazer sets this code soon as you start it,It came in yesterday after noon and looking at codes it also had acode for the transmission shift solenoids,road testing reveiled car was taking off in 3rd gear replacing the solenoids corre... Trouble codes: PO601 (pcm memmory error).		 View
1992 GMC Yukon 5.7L electronic hydraulic control unit
Hello fellow Techs, I have a 92 yukon here with 4 wheel abs and have code 61 stored.I have followed the shopkey flow chart for this code and it tells me to replace unit(almost $1400.00 here in Canada)The customer tells me the abs light came on after an extende...		 View
1992 GMC Sonoma 4.3L hard start
This vehicle came into our shop the first time in Sept. 2006. It was towed in as a no start. I checked the vehicle and found it had no injector pulse because both ecm fuses were blown. The cause of the blown fuses was the injector connecter wires were brittle ... Trouble codes: 55 (prom fault), 54 (fuel pump circuit low).		 View
1995 GMC Jimmy 4.3L 4wd
tested vaccum lines from trasfer case to acuator under battery,lines are good & holds vaccum ,acuator under battery will work if i apply vaccum ,replaced vaccum switch on top of trasfer case 4wd light just flashes then goes back to 2wd mode ,all fuses are good...		 View
1997 GMC Pickup 5.7L MIL Lamp on
The MIL lamp comes on every month on this vehicle and the owner thinks there is a big problem. The OBD II scanner erases the code and turn the MIL lamp off for about a month. What can I do to stop this? My thought is to replace the O2 sensors or cat.		 View
2000 GMC Sierra 5.3L No Start, Poor Idle Quality, Stall
Vehicle came into shop for intermittent stall and rough idle. The conditions only occurs at startup. No surging or rolling idle just runs rough or stalls for first 30 seconds. No codes/No Misfires found and fuel pressure within spec while problem occurs.		 View
1995 Oldsmobile Cutlass Ciera 3.1L Blower Motor
Hello all. We have this 95 Olds Ciera that keeps blowing the blower motor fuse. Originally came in and the ground wire was disconnected so we connected that and fuse still blew. Customer already had blower motor installed at another shop. Tried a blower motor ...		 View
2001 Oldsmobile Intrigue 3.5L MIL Lamp on, SECONDARY AIR PUMP
hi guys, we have re routed the fresh air intake side of this due to water intrusion before and we still are getting enough water out of it to fill a coke bottle. has anyone run into this before and if so what did you do to resolve? thanks in advance. Trouble codes: P0410 (secondary air injection).		 View
1998 Pontiac Firebird 3.8L No Start
Cranks and will not start. Had no tach signal. Pulled #6 plug wire off at coil to check for spark and engine started. Did have a screw driver laying next to coil tower when it started. Bravely and carefully we reconected plug wire to coil and it stays running....		 View
2003 Pontiac Grand Am 3.4L no start
customer brought in car. car sat in parking lot for 10 minutes. got ready to bring car into the bay and car would not start. getting ready to scan and the car started up. could not get this car to act up again. hooked snapon modis to bcm data 2. test results--...		 View
2000 Saturn SC2 1.9L Clutch Master cylinder
We had a low clutch pedal, and slight fluid lead out of the clutch master cylinder. Replaced clutch master cylinder, but now can find no place to bleed slave cylinder. We tried pressure bleeding cluch, but did not work. I see that Saturn only sells this as a...		 View
2004 Saturn Vue 2.2L transmission
Customer complains of intermitent no drive or reverse.Sometimes at a stop light or cruising the trans suddenly has no forward gear.Turn off vehicle and wait ten minutes and then OK. I cannot duplicate the problem. customer has had the vehicle back to dealer a ...		 View

Fixes & Summaries for GM
Fix/Summary Answers
1993 Buick Century 3.3L Excessive Emissions, No Start, Poor Idle Quality, Surge, Cuts out, Stall, Misfire
it was the crank sensor causing this condition. sensor scoped ok. when we pulled balancer we saw a new aftermarket sensor hade been installed prior to us getting this car. replaced with ac delco car is fixed. weird thing is car ran bad cold and the hotter it g...		 6
1998 Buick Regal 3.8L abs
Thanks Brian, Shawn, & Kris. Hub and bearing assembly fixed this one. Amazing how the speed on the scanner was correct but still set a code. Thanks to all that replied.		 8
2000 Buick Regal 3.8L No Start, Cuts out, MIL Lamp on
Ignition switch fixed all problems.Loss of 12 volts on the pink wire from the switch,bad contact in switch.Found while rechecking fuses,found low voltage on the turn signal fuse,followed schematic back to Ign.switch,found low voltage at switch.Replaced switch,... Trouble codes: U1000 (communication problem), U1040 (ebcm communication problem).		 9
1997 Cadillac Eldorado 4.6L traction control system
Well this one isn't fixed as yet. We are waiting for the customer to return so we can continue diagnostics. I suspect that there is a faulty wheel speed sensor which is of course a hub bearing assy. The complaint is more predictable after a bumpy rear surface ...		 9
1995 Chevrolet Monte Carlo 3.4L No Start
Thanks to everyone who responded and for all the advice. I was the second technician to look at the car. I also suspected the anit-theft system, but the security [...] did go out and did not flash. I did remove steering wheel to check the 2 wires on the lock c...		 26
1996 Chevrolet Express 5.0L rear brake lamp
hi thanks for all the help, replaced rear lamp circuit board and fixed it.		 33
1997 Chevrolet Blazer 4.3L No Start, Stall
I got the Blazer in this morning. Installed ign switch . Thanks for all the help. Dan		 63
2002 Chevrolet Astro 4.3L Misfire
Most of the replies I received said to remove the vent screens in the distributor and check the ac low pressure hose and make sure it's insulated good. It all makes sense to me and I will try it. If I have anymore problems with this one I will post it. Thanks ...		 14
1997 GMC Sonoma 4.3L unkown
This truck is fixed. Sorry I didn't tell you guys that this is a 2wd in my post but with your help I was able to fix it anyway. Yes as Lynn from LA suggested this truck had a New River Driveshaft. I started focusing on the driveshaft and as I remembered in my ...		 15
2004 GMC C8500 7.2L Oil System
First i would like to thank the three people who have replied. I really appreciete the time. All responses were for an internal engine problem which I can understand..from sludge build up to blow by issues .I even got a phone number for a CAT dealer up north. ...		 3
1993 Pontiac Grand Prix 3.1L Hesitation, Surge, MIL Lamp on
I cant call it fixed, but its gone. Several suggested using the 'legacy' software as opposed to the cartridges. Most reported to check powers and grounds at PCM. I tried my scanner on my own 94 Caprice and all was fine--cant fault the software in my scanner. D... Trouble codes: multiple (setting randomly).		 10
2001 Pontiac Grand Prix 3.8L power steering
Would you believe (and I'm sure you will) , we went through 3 pumps before we got one up to spec. and ... through 3 racks before we got a good rack (the two the customer supplied were both no good , so a new reman. rack did the trick .I know this was straight ...		 15
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