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Open Help Requests for GM
Help Request Answers
1941 Buick roadmaster 322CID radiator
car is in very good condition overheats to 210 deg in 4-5 minutes driving or 8-10 if running in shop , water flushed to check for sludge etc ,none fairly clean no air bubbles in coolant , does anybody know if any of these straight 8, engines used a water distr...		 View
2000 Buick LeSabre 3.8L All Windows Door Locks Mirrors And Interior Lights
Has anyone had anything like this or seen this before. Sometimes I have power to door switch most times not. Either way nothing works. Any Ideas?		 View
2002 Buick Rendezvous 3.4L no crank / no run
This car came in a month ago for no crank, found fuse # 27 blown, fuse 27 is ING Main, replace fuse runs great. customer drove for a month, today the car died and wouldnt start. upon inspection fuse # 27 was blown again, put in another 10 amp fuse, no problems...		 View
1992 Chevrolet Pickup 4.3L No Start
Thanks for taking the time to read my post. We are having problems with this throttle body injection C1500 truck with manual trans.. We know that the pulse width at the injectors are too low. Its at about 2.00 milliseconds during starting when we think it shou...		 View
1994 Chevrolet Lumina 3.1L No Start, Cuts out, Stall
Help me guys! I have been working on this car for two weeks. It keeps losing spark after you drive it for a couple of days. I replace the ignition module and it starts and runs fine for me. The owner will come and pickup and drive and it dies or no start. The ...		 View
1994 Chevrolet S10 Blazer 4.3L Excessive Emissions, Poor Idle Quality, Hesitation, MIL Lamp on
Vehicle will not communicate with scanner but will flash a code 12 with no other codes. Check engine light stays on. Trouble codes: 12.		 View
1996 Chevrolet Blazer 4.3L Hesitation, Cuts out, Misfire, MIL Lamp on
vehicle came in on hook cust complained of lack of power and popping noise through intake. cust stated that he replaced the fuel pump one year ago due to sugar in tank... i had noticed that the heater core hose was dripping coolant on the dist cap and coil wir... Trouble codes: po151 (ho2s 11 low voltage), po133 (ho2s 21 low voltage).		 View
2001 Chevrolet Suburban 5.3L MIL Lamp on
have a 2001 suburban here that 02 sensor will read low when 02 sensor warms up, reads okay when cold, replaced cat with one from carquest and same problem, replace again with one from napa and same problem, run b1 s2 harness to b2 s2 sensor and reads fine. 02 ... Trouble codes: PO137 (02 signal low bank 1 sensor 2).		 View
2001 Chevrolet Express 5.7L Hesitation, Surge, Cuts out, MIL Lamp on
Van originally came in MIL on Scanned & TPS replaced as it was bad. 2 weeks later van back with MIL on, Scanned & found P0101. Cleaned Maf & code returned. Replaced Maf (OEM) & code still returns. Test drive & code will set in about 1km. Mil comes on at second...		 View
2002 Chevrolet S10 Pickup 4.3L Misfire, MIL Lamp on
Hello everyone, I'm working on this vehicle thats got me a bit stumped. It came in on the hook due to it was run off the road and into a pond. Water came into the vehicle to the base of the seats (not over) and was hydrolocked. I pulled out the plugs and dried... Trouble codes: P0300 (Random misfire detected).		 View
2003 Chevrolet Tahoe 5.3L Hesitation, Stall
Thanks in advance for any help, this one is a nighmare, I have a Chevy Tahoe that intermittently, cuts out, or stalls. When it does there is a chime, the doors unlock and relock, the radio has a Ipod hook up and it kicks the Ipod off and turns back to radio, t...		 View
2005 Chevrolet Monte Carlo 3.4L Misfire, MIL Lamp on
hi all. this car came in with customer complaint of ses light on and does not shift into 4 th gear. perorm scan test found p0300 cylinder miss fire code in system, when monitoring miss fire data on scanner no 6 cylinder misses continuasly. inspected spark plug... Trouble codes: P0300 (cylinder miss fire detected).		 View
2006 Chevrolet Uplander 3.5L no crank
Customer stated vehicle will not crank over after she has driven it and stops to go in store. She states it always starts fine in the morning when the vehicle is still cool. We found the vehicle does start fine after it has been sitting. Once it is heated up i... Trouble codes: U1000 (Class two serial communication error).		 View
2006 Chevrolet Malibu 3.5L Unknown
car came with sticking brakes on all wheels. it only happens once a month or twice a month. wondering what could be the possibility? as soon as you let it sit for a little bit, it will be back to normal. i felt the brake pedal to be very hard when the brakes s...		 View
2002 GMC Envoy 4.2L engine
engine vibration all the time in park or drive, pry on left of eng vibration minmizes.Removed belt vibration still there,balancer does not seem to be bouncing all over the place.Just wore out?Please help!		 View
2003 GMC Envoy XL 4.2L blower motor
Hello fellow techs. This vehicle has two issues. The first is the blower motor (when it works) stays on after you turn the igniton off and remove the key. It will run for(5-10min.) after the key is out. I replaced the ignition switch after looking at some othe...		 View
2003 GMC Sierra 5.3L ac controls
Hello and thank you in advance for any help I can get.This truck ac was working just fine until one of the sales men put in a battery now the ac only comes out the defrost vents I have checked all volt wires and ground wires at ac controls and at mode door act...		 View
2005 GMC Canyon 3.5L abs
Customer states that on two(2)seperate occasions,dry conditions,travelling down the interstate,one time 65mph and the other time 50mph, his Canyon steered or veered and did a lane changed on its own.He also stated that the truck tried to fishtail.He was not ap...		 View
2001 Oldsmobile Silhouette 3.4L Surge
HI. This engine has a 200rpm surge, and no misfires, about twice a second under light load/accel when running between 40-60 mph in high gear, TCC lock. The two codes shown do not relate to the problem: the trans adapts show up once in a great while, and the Ev... Trouble codes: PO449 (evap system), P1811 (max adapts long shifts).		 View
2001 Pontiac Grand Am 2.4L Engine
This car has a vibration like the harmonic balancer is bad. I canged it even though it looked ok because I didn't have any other ideas as to what it could be. At idle it has a very bad vibration. It doesn't vibrate at higher rpm's and doesn't miss it just ratt...		 View
1997 Saturn SC1 1.9L Shift
this car has blown off 2 carquest filter and one saturn filter. The first one was put on after a flush. the car came back complaining of hard shifting then blow off filter gasket. I got it in replaced filter and replace the valve body with new solenoids. reset...		 View

Fixes & Summaries for GM
Fix/Summary Answers
1998 Buick Park Avenue 3.8L High Idle Speed
The ECM was defective. I think the key was the RPM was 2800 but desired RPM was 700 on the scan tool. But the ECM happy enough to not set a code. When I flashed the second ECM the MIL was on with a "crank not learned code". The defect wouldn't finish crank rel...		 11
1986 Chevrolet Corvette 5.7L air condition
Got 17 replies.Most said to retro fit to 134.Some said LIABILITY and LITAGATION.Not approved for mobile a/c.Not legal in cars.Contaminates yours and others machines.Not on EPA snap list.One reply used 416 for 2 years with no problems.One mentioned 402b as a dr...		 17
1997 Chevrolet Astro 4.3L Excessive Emissions, Poor Idle Quality, Surge, Cuts out, Stall, MIL Lamp on
PLEASE SEE MY ORIGINAL POST. REPOSTED ORIGINAL POST AND ADDED MORE INFORMATION JULY 22 2008. THANKS DAVE		 7
1997 Chevrolet Tahoe 5.7L Misfire
After reading what some had suggested I performed a running compression test and found the cylinder 60Lbs@ idle and 30lbs@ 2000 RPM. I decarboned the engine with GM's Top Engine Cleaner due to the fact that I found so much trash on the spark plug. After the ... Trouble codes: P300 (Random misfire), P304 (4 misfire).		 24
2000 Chevrolet Astro 4.3L RAP (retained acc. pwr)
thank you to all that responded! it turned out the rear slider door switch was at fault. nicely worn on the end. a whopping 7 dollar part not included in the diagnostic chart... anyways, the locks all work now, except the actuator for the passenger door. thank...		 5
2002 Chevrolet Malibu 3.1L Poor Idle Quality, Surge, Misfire, MIL Lamp on
hi all . i retested compression - ok , did leak down test - ok , rechecked spark plug wires , replaced fuel pressure regulator and all fuel injectors with a good set of used ones. customer took car back because she needed it for work . came in yesterday and sa...		 7
2005 Chevrolet Equinox 3.4L steering
WELL REPLACING THE POWER STEERING UNIT UNDER THE DASH FIXED THE NOISE ONE THING TO BE CARFULL OF IS YOU MUST HAVE THE STEERING REPROGRAMMED AFTER REPLACEMENT. SERVICE VEHICLE LIGHT COMES ON AND CANNOT BE TURNED OFF WITH SNAP ON OR OCT SCANNERS		 4
2007 Chevrolet Uplander 3.9L Rear Suspension
There is a TSB for the rear trailing arm bushings. Even if they look good they can still cause problems. This was what I originally thought. The van is under warranty and we are a fleet shop so we sent it back to Chevy with a copy of the bulletin. They've had ...		 4
1992 Pontiac Sunbird 2.0L Engine
I didn't get much help on this one, only 4 replies that basically said it's not worth fixing. I'm trying to find a used motor for the car.		 4
1997 Pontiac Bonneville 3.8L starter
Sorry it took so long to close. Customer took car since it is not acting up and has not been back. I had a lot of replies about the ignition lock cyclinder and a couple on the P/N switch. I was not comfortable changing either since I could not get it to act...		 9
2001 Pontiac Bonneville 3.8L A/C Temp
We recharged the system and added dye this time. The customer returned yesterday with no A/C. After inspection, we found dye around the front of the compressor. Hopefully this will resolve his issues.		 8
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