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2002 Buick Century 3.1L abs module
performed diagnostics tests for abs code c1214;powerand ground and resistance tests all show good . troubleshooting chart led to replacing abs module.abs light remains on and now there is no communication under abs with genesis scan tool		 View
1993 Cadillac Seville 4.6L No Start
I have this 1993 caddy seville sts with a 4.6 northstar engine towed in for a no-start. Since this thing was flooded I decided to check the fuel pressure regulator. When I took the top off there was about a gallon of fuel in the engine, but upon checking, it w...		 View
1996 Chevrolet Pickup 5.7L Surge, MIL Lamp on
Hello all, thanks in advance for any help I may recieve. This vehicle cam in with the mil light on and a surge while cruising. Performed complete tune-up along with a distributor. The distributor is lined up correctly. The cam retard is a bit unusual though, m... Trouble codes: 1345 (distributorcrank sensor correlation problem).		 View
1999 Chevrolet Pickup 5.7L No Start
Replaced the engine on this truck due to rod knock + blown head gasket. Engine cranks fine; no start. Thinking bad distributor teeth. It's killing me because I have everything I should need to run. Made sure passlock system not being triggered. I have EVERYTHI...		 View
1999 Chevrolet Malibu 3.1L Stall, Misfire
After replacing intake manifold gaskets to stop water leak engine would backfire and barely run. Can keep engine running only with open throttle, but it backfires randomly. We checked that pushrods are installed correctly, checked all connections and vacuum li...		 View
2001 Chevrolet Cavalier 2.4L transmission
This car belongs to the wife of one of our techs and he needs help! lol The transmission suddenly stopped going into reverse. The fluid level and condition is perfect. There are no codes. The linkage works fine. It shifts perfectly in all forward gears. It mak...		 View
2002 Chevrolet Camaro 5.7L Misfire
This vehicle came in with a check engine light on, and I found two codes. PO300 random misfire and PO420 catalyst efficiency bank 1. I found and repaired the vacuum leak on the pcv harness. I also found a dirty MAF sensor (K&N), I cleaned the sensing elements.... Trouble codes: PO420 (Catalyst Efficiency Bank 1).		 View
2004 Chevrolet TrailBlazer 4.2L reduced power light
This trail blazer has a "reduced engine power" light on, and very limited accelerator function, I can only accelerate to 30 MPH. A code P1680 is also set, Alldata flow chart says to replace the PCM, no tests, just replace and program. I am not sure what the "d... Trouble codes: P1680 (Driver 5).		 View
2005 Chevrolet Express 6.0L abs module
now what happens which may not be related is after drive only over a very rough road, all dash gauges peg and fluctuate, abs light and brake light comes on and warning chimes sounds about six times, than bcm codes b1420,b1440,b2961 and abs coo55 are set, we ch...		 View
1996 Geo Tracker 1.6L lack of power
Hi guys, This vehichle starts and runs, but has a severe loss of power. It will rev up in park, but not real well. Put in gear and it barely is driveable. Thought for sure the exhaust was plugged, but I dropped the pipe and no difference. Checked timing belt a...		 View
1999 GMC Yukon 5.7L wipers\power windows\radio only
GM Techs we need your expertise on this strange electrical malfunction- the wipers\power windows & radio stop working and no power to affected fuses for these circuits.Checked wiring diagrams for these circuits & see no common denominator.May be reading the ch...		 View
2000 GMC Pickup 7.4L back fire on start
hello, well this truck has plagued me for a year now.i repair veh. for a living but cant seem to figure out my own,this is my truck.with in the last 6 years this thing has eaten injectors on a regular bases.a full set every 15 to 20k.they have all been gm.but ...		 View
2005 GMC Yukon 6.0L Steering
Alignment shop said alignment was good and suspension was good, pull was likely from tires.. i rotated front to back thn left to right and still have same pull "to left" any problems with gear boxes seen on these...tires are 265/70r17 bridgestone dueller AT .....		 View
1994 Oldsmobile Cutlass Ciera 3.1L Poor Idle Quality, MIL Lamp on
Greetings fellow techs, Got this 1994 Oldsmobile Cutlass with a 3.1 V6 in today running rough and MIL light on. Checking codes I came up with a PO321-Ignition Control 24X Signal Circuit. After taking a look, I noticed that one of the wires leading to the crank... Trouble codes: PO321 (Ignition Control 24X Signal Circuit).		 View
2003 Oldsmobile Alero 3.4L No Start
This problem has been very difficult to diagnose as it occurs very intermittently. Today it did it twice which was the first time in 4 days. When the problem occurs the green/white wire from the pcm to the fuel pump relay goes dead, no fuel pump. At first I th... Trouble codes: B1001 (Air Bag code - communication problem), B2585 (BCM code), B2752 (BCM communication code), U1000 (BCM communication problem), U1255 (IPC communication problem), B1365 (circuit problem).		 View
1990 Pontiac 6000 3.1L Excessive Emissions, Poor Idle Quality, Surge, Cuts out, Stall, Poor Fuel Economy
Read previous history first. Came back in today (done 175km since in last), understandably customer is not thrilled... Same codes came back up (refer list), we do not have a gas sniffer or an ignition scope, so here goes. Engine runs rough at idle, same when c... Trouble codes: 35 (Idle air control IAC problem), 45 (Rich exhaust), 44 (Lean exhaust).		 View
1997 Pontiac Bonneville 3.8L Starting
Ok this is my first session getting on here. I need HELP. This vehicle is having problem with security light coming on and vehicle not starting intermitant. This problem has been happening for a couple of years know. Firts thing i did was bypass lock cylinder ...		 View
1999 Pontiac Firebird 3.8L Misfire
hi this is michael from stewarts automotive in sacramento. we have gotten a 1999 pontiac firebird with a misfire issue. scanned for codes got a p0300 random misfire, thats it no cylinder number or any other info. drove the car on the freeway 60mph or so it wou...		 View

Fixes & Summaries for GM
Fix/Summary Answers
1977 Chevrolet Blazer 6.6L rings
Thanks to all who replied to my request. Many said the rings were probably good since the cylinder walls were clean with no scratches or gouges. One interesting reply said to buy a 4 inch rubber inside pipe plug and drill a hole through it and put a fitting ...		 29
1995 Chevrolet Cavalier 2.2L Poor Fuel Economy, no power
The fuel pump was bad but the timing chain tensioner guide allowed the timing to jump one tooth. All though the customer declined the rapair I take my hat off to the helpful information from the ATN group. Thank you		 7
1997 Chevrolet Camaro 5.7L MIL Lamp on
This is one of those situations that is going to require more time to know for sure whether the problem is indeed fixed. I ended up removing the fuel tank and pump. The vapor line leaving the tank does have a check valve built into the pump: It is a float i...		 7
1998 Chevrolet Pickup 7.4L Steering and Brakes
Thanks for all of the responses, the problem was internal to the power steering pump. I made an educated guess since both the steering and the brakes had the vibration sensation I assumed it was internal to the pump, indeed a new pump fixed the problem. Than...		 6
2004 Chevrolet Silverado 6.6L Light
We ended up taking this to the local dealer. They said they have never heard of this problem. They did the same thing we did they tried the 10 minute relearn, the 30 minute relearn, also tried flashing the PCM, IPC, Reflashing the BCM And running the 10 & 30 m...		 4
1984 GMC 7000 4.9L engine brake
after trying to find adiagram dealer told me no diagram available had customer bring truck back followed harness all the way back repaired open thanks again		 3
1986 GMC C7000 7.4L Hesitation
hey its fixed,sorry it has taken so long to get back to this. had to have the throttle plate bushings replaced again. tech at carb shop said to be sure not let the base idle screw close the plates all the way, they will stick for sure if the plates close. so a...		 4
1996 Pontiac Bonneville 3.8L Headlamps
This vehicle is fixed! Glen was right on the money, I started by unplugging each of the components and when I got to the headlamp control module, the lights went out. The module was on the firewall in the middle right on the floor, a bit tight but not to bad t...		 7
2000 Pontiac Bonneville 3.8L Stall
Thanks to everyone for helping. I received good information from you all. I found the Fuel Pump Control Module on this car to be bad. The Unit is located in the trunk on the right side behind the trim panel. The unit from this car was physically damaged. It lo...		 21
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