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Prev Professional Automotive Repair Technical Discussions for July 6, 2005
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Open Help Requests for GM
Help Request Answers
1950 Buick roadmaster 229CID master cylinder VIN: 0075873511
Hi all,this one has us stumped.When you drive this car for about 30 -50 miles the brake system builds up preasure to the point when you apply the brakes it lockes up all the wheels.the only way you can move it is to release the preasure at the wheel cylinders....
1993 Cadillac DeVille 4.9L Compressor VIN: 1G6CD53B9P
Hello, This vehicle's A/C compressor won't engage on it's own. The compressor is not getting the ground from the PCM to the A/C Compressor Relay on the LT GRN/BLK wire (ckt 366). I can supply the ground and the compressor engages and works fine. According ...
1997 Cadillac Seville SLS 4.6L stability system VIN: 1G6KS52YXV
Car has a "reduced stabilty" warning displayed in the message center. I have retrieved codes C1252, C1253, C1282 and C1285. I would like to test the components that are related with these but my ALLDATA doesnt give the right locations. I need help finding the ...
1984 Chevrolet K5 Blazer Custom 5.7L Excessive Emissions VIN: 1G8EK18L7E
Help I have this K-5 full size Blazer in the shop and it is failing the emissions test for NOX. I replaced a known bad TPS to no avail. My problem is I dont have the proper wiring diagram. The EGR solenoid is never being commanded to pass vacuum. Even with the...
1990 Chevrolet Lumina 3.1L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire VIN: 2G1WL54T5L
vehicle ame into our shop with a no start condition. performed routine diagnostics and found that there was no injector pulse. determined that ignition module was bad and replaced. vehicle starts ok most of the time. seems to have loop at idle. checked for any...
1994 Chevrolet K3500 Cheyenne 6.5L Excessive Emissions, Cuts out VIN: 1GCHK39F3R
need some help ok here goes truck came in with a acp code i believe it was a 84 replaced acp module also had a code 78 here is were it gets to the guestion the tech 2 scanner i am using shows boost pressure at 14 lbs at idle under a load will rise to over 20 h... Trouble codes: 78 (wastegate), 88 (tdc error)
1995 Chevrolet Camaro 3.4L Poor Idle Quality VIN: 2G1FP22S4S
Hey guys, I have this Camaro with no signal coming out of the crank sensor 24X sensor. The other crank sensor is operating correctly. I have ignition voltage and proper ground to the 24X sensor, but no signal coming out. Actually, 400mV AC is going to the comp... Trouble codes: 36 (24X signal error), 43 (knock sensor signal error)
1997 Chevrolet Cavalier 2.2L No Start VIN: 1G1JC5245V
came in running for smog ck .failed for ses on above codes ...lowered pcm and did tap/wiggle test unplugged pcm inspect for corrosion none 3 ground under bat major rust. one disconnected clean and connect ... car never started and RAN again ...anti theft light... Trouble codes: P1601, P0118, P0122
1998 Chevrolet Lumina 3.1L MIL Lamp on VIN: 2G1WL52MOW
Hello again we have this lumina here that came in for a check engine light runs bad complaint. found code p0300 random misfire and p1381 misfire ebcm. we figured 102k and all original tune up stuff was probably a good place to start replaced plugs and wires wi... Trouble codes: P0300 (random cylinder misfire), P1381 (cylinder misfire ebcm/ ebtcm)
1999 Chevrolet K2500 Suburban 7.4L 4x4 VIN: 3GNGK26J8X
This is a post for the tech who works next to me, so I will give you all info that he relayed to me. truck came in for 4x4 inop, Service 4x4 light on. Began testing and found fuse #2 for T-case blown and fuse for 4x4(dont know fuse #). Code U1026 stored. He re...
2002 Chevrolet Silverado 2500 HD 6.0L fuel gauge VIN: 1GBJC3YU52
Fuel gauge reads empty. Low fuel light is on, always. Fuel gauge will react to Mastertech, when commanded. Rear level sensor reads 2.35 volts, 78% remaining. Front sensor reads 1.86 volts. Information on percentage not given for front tank. If either sensor is...
2003 Chevrolet Tahoe LS 5.3L unknown VIN: 1GNEK13253
hello, everyone. i'm sick of this one. we have an 03 tahoe that will, without fail, make a noise like a plastic bag wrapped around a driveshaft during cold accelerations/takeoffs at roughly 15-20 mph, but only once, and will not occur again until cold. we've r...
1972 GMC C2500 350CID overflow tank VIN: TCE2421522
hey folks , I have a sneaky feeling I'm overlooking something but I don't think so .This truck has a newly rebuilt motor and trans.Problem is that coolant will purge into the overflow but won't suck it back .Have tried a few new caps ,no leaks ,tests negative...
1990 GMC Top Kick 366CID Excessive Emissions, Poor Idle Quality, Cuts out VIN: 1GDL7H1P6L
This truck was brought in from another shop. It would not Idle or accelerate without backfiring through intake. They had replaced the distributor, D. cap, rotor, plugs and wires . Still had same problem, then they replaced the pcm. Still the same. Then the tim...
1999 GMC Sonoma SL 4.3L Surge, Poor Fuel Economy VIN: 1GTCT14W1X
OK I need some help on this truck,the motor was replaced in this truck because of the man ran it hot until it cut off on him ( has been carry around water to put in because of the water pump leaking and I guess he forgot to add some before this trip)it came fr... Trouble codes: P0410
1995 Oldsmobile Aurora 4.0L Accessories VIN: 1G3GR62C6S
I have a strange one here, when you turn on the lights or use any electrical items you get a beeping noise from the dash. I have checked the alternator and battery for any concerns but both seem ok. This car has a message center but everything is ok so I don't...
1996 Pontiac Sunfire SE 2.2L growl inl/f area during stop, 30-10km VIN: 1G1NL64W7T
was hoping some has ran across this before, I suspect a diff bearing...But the sound and vibration does not resseamble one... It is only heard and felt on decell, comming to a stop. Under 20km per/h There is no problem on accelleration, or high speed driving. ...

Fixes & Summaries for GM
Fix/Summary Answers
1996 Buick Century Custom 3.1L cooling fans VIN: 1G4AG55MT6
Good morning to all. I would like to thank everybody that has sent me help on this buick. I must say that I still have not fixed the car to this date but I will close this tech request for now and will repost when I find the problem. Thank you all for helping ...
2002 Buick Century Custom 3.1L Compressor
Thanks to those who replied to my help request. Brian inquired as to any codes - there were none. Jason from Australia suggested evap temp switch - doesnt have. Erich suggested resetting the memory & this was done repeatedly. Mike from Iowa inquired as to the ...
1989 Chevrolet Corvette 5.7L fan VIN: 1G1YY2180K
we replaced the ecm this took care of no fan with engine temp,however the groups suggestion of replacing the fan control switch in the high side a/c line near the evaporator did repair the no fan with a/c compressor problem,once again thank you so much for all...
1991 Chevrolet C1500 Cheyenne 5.7L airflow VIN: 1GCDC14K2M
Well folks, I finally found the time to look at my truck, and sure enough, the evaporator was completely clogged with little styrofoam beads. I took the advice of most of the respondants and removed the blower motor to access the front of the evaporator. I rem...
1992 Chevrolet S10 Blazer Sport 4.3L Low power VIN: 1GNDT13Z1N
This customer did not want to put any more money into finding this problem, he has decided that this vehicle is just a dog with poor mileage, as he puts it. The vin Z motor is common for a few things i have been told through the replies i recieved. Cracked dis...
1994 Chevrolet P30 Box 5.7L Drive train VIN: 1GBGP32K2R
It is fixed I don't know exactly what did in fact fix it. I replaced all of the u-joints and the center support bearing. They had been replaced before and did not show any wear .I took the cover off of the differential but could not find anything unusual. The ...
1995 Chevrolet Camaro 3.4L Cooling Systems VIN: 2G1FP22S8S
As pretty much everyone who replied stated, check the radiator cap for proper pressure rating!! The cap was replaced with the cooling system flush, however the parts boys did not tell us that there are two options for the pressure rating! As the replies specif...
1996 Chevrolet C1500 4.3L Starting VIN: 1GTEC14W4T
Thanks For the many replies for my problem, The truck was here over nite & of course it started right up, all sensors were reading good before start up & fuel pressure was 61 lbs koeo. Got a break this time it had 2 codes in it---map too high & crank sensor ...
1996 Chevrolet Express 2500 5.7L No Start, no injector pulse VIN: 4KLB4B1R0T
thanks for the help on this. by replacing the vcm & cleaning the grounds i picked up the injector pulse. the fuel pressure was 50 lbs which i found out was not enough. i replaced the fuel pump & now have 55 lbs of pressure. truck is fixed. thanks again!!!
1997 Chevrolet Lumina 3.1L Brakes VIN: 2G1W152M8V
It turned to be a defective booster from the auto parts store, we installed a new from dealer, and the car is just fine now , no more brakes locking up, aparently the old had an internalleak so it was building up pressure internal to the point of self activati...
2000 Chevrolet Cavalier LS 2.2L No Start VIN: 1G1JF5242Y
I want to thank everyone who took the time to help me. I never totally repaired the problem. I was able to make the car drivable. Almost everyone that replied seemed to be referring to the tsb about the faulty sending unit that G M was replacing on some of the...
2001 Chevrolet S10 2.2L Hesitation, Stall, MIL Lamp on, HIGH IDLE VIN: 1GCC14581K
Thanks to everyone who replied to my help request. I'd like to say that I checked everything that was suggested and did not find anything out of spec or bad. The truck is now back in service but will return to our shop for further diagnosis when time allows. T... Trouble codes: P0108 (map sensor circut high input), P0122 (tp sensor circut low input).
1987 Pontiac Fiero SE 2.5L Poor Idle Quality, Hesitation, Surge, Stall, Poor Fuel Economy VIN: 1G2PF11ROH
Thanks to Keith, Alfred & Gerry. The fix ended up being a leaking pressure regulator in throttle body. Special note to Rusty who left me an e-mail. I didnot post all sensor readings because they were correct. The ones I did post were wrong. I do not apprecia... Trouble codes: 45 (rich exhaust).
1996 Pontiac Grand Am GT 2.4L reverse gear, 2nd , 4th gear VIN: 1G2NW12T1T
Thanks to all who responded, the fix was a new shift cable for the forward and rearward motion of the shifter. The outer housing had split under a rubber cover which effectively shortened the inner wire travel. It wasn't readily obvious until we cut the rubber...
2002 Pontiac Grand Prix GT 3.8L Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1G2WP52K72
OK after several aftermarket mass air flow sensors we decided it was time for an ac delco sensor however when it arrived it was in a remanufactured box with an ac delco sticker on the box it had the same stickers and marking as the aftermarket ones so we decid... Trouble codes: P0102.
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