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Help Request Answers
1989 Buick Reatta 3.8L No Start
I have a strange one here. At times (intermittently) the coolant sensor will go to 306 degrees, IAT will go to 299 degrees, EGR will stars clicking, Many relays will start clicking, IAC motor will start moving. When problem goes away everything starts working ...		 View
1995 Buick LeSabre 3.8L volt light
according to shop key the alt. is controlled by the pcm. i have power to the pcm from the volt light but no power coming from pcm to alt. "l" terminal. checked wire resistance--ok. should i replace the pcm or is there something in my schematic missing. thanks ...		 View
1990 Cadillac DeVille 4.5L blower
vehicle has no ac information, or fuel info. no lites. cant access trouble codes from ac controls. all fuses are good. power to ac module at red wire . no power at purple, has good ground on black to module. when calling ask for michael please. thank you.,		 View
2001 Cadillac DeVille 4.6L abs & traction lights
Hey guys got a real stumper here. Another facility diagnosed this as a bad ECBM, customer brought this vehicle here with the paper work from a Cadillac dealer. We replaced the ECBM & flashed the ECBM. Now after all the programming we have codes C1248 EBCM Turn...		 View
1977 Chevrolet Corvette 5.7L water valve
This vehicle came in with no change in direction of air flow. The vacuum portion of the heater, a/c control was not functioning. This I replaced and now have switching of direction, but when switched to off there is a flow of hot air. I found that there is no ...		 View
1993 Chevrolet Pickup 5.7L MIL Lamp on
truck was towed in.found fuel pump dead.raised truck bed to replace fuel pump and strainer.also replaced fuel filter.took on 20min test drive,drove great.called customer told him truck was ready.customer picks up at closing time,calls 10min after picking up an...		 View
1995 Chevrolet Camaro 5.7L No Start, Stall
Customer drive rpm will rise and fall then engine will stall. Or customer will drive for awhile and shut off and try to restart will not start. let set for awhile and starts up. Trouble codes: 16 (Low res. pulse circuit), 33 (MAP sensor circuit high), 36 (High res. pulse circuit).		 View
1995 Chevrolet Cavalier 2.2L Poor Fuel Economy, no power
customer complained of misfire and stalling. Found that fuel pressure was at 19 psi (recommended spec, 41-47psi) no codes found replaced fuel filter with no change in pressure. Replaced fuel pump assembley fuel pressure now normal misfire is gone and vehicle d...		 View
1998 Chevrolet Suburban 5.7L vent tempature
I need some advice here.When I checked the A/C out on this suburban It had no freon in the system due to a leaking compressor.I replaced the compressor with a brand new Delphi unit,drier and orphis tube.I added 8 0z of pag oil pulled a vacuum for 45 min and ch...		 View
1999 Chevrolet Blazer 4.3L cluster
This 99 will display the prndl and odometer only when the key is in unlock and crank. when turned to run from unlock the displays go out. Then if you hold the key in the right spot during crank it will come on again. Vehicle is from used car lot so other histo...		 View
2000 Chevrolet Impala 3.8L dash lights and abs
Hi IATN.this car came in with intermittent turn signals,the flasher in hazard switch contains the flasher unit,and buzzes when the turn signal is turned on,no turn signal operation,and the dash warning lights come on.And although I have not felt it,the custome...		 View
2003 Chevrolet Impala 3.8L cyl #2
this car is cracking the number 2 spark plug after about 100 miles of replacment... i think the problem is high comprssion in that cyl... at 180lbs... but i wanted to see if anyone else has seen this and had any luck with a somewhat simple fix?? thanks in adva...		 View
2004 Chevrolet Silverado 6.6L Light
Truck Came in with multiple sysptoms ( rear windows not working, Instument cluster illumination not working, Servoce 4wd light on, Service ABS, Front Power windows only work when Truck is running - not working With KOEO ) Had no Comunication with BCM. This tru...		 View
2006 Chevrolet Colorado 3.5L Poor Idle Quality, Misfire, MIL Lamp on
Hello folks - I have a strange chevy with an intermittant misfire on cyl #5. I have changed coils and plugs between cyls and no change. Compression is 130psi on all cyls. The misfire monitor is going nuts on #5 and cannot find why. There is apparantly no vavum...		 View
1995 GMC 3500HD 6.5L turbo boost
Hello diesel guys. This customer (concrete mason) has a number of vehicles that we service. Two are diesels and we don't do much diesel engine work. The symptoms were multiple. First, there was a serious exhaust leak at the left side manifold. this was repai...		 View
1998 GMC Pickup 5.7L brakes
Customer complained of poor brakes and pedal going to floor pedal pulsing when coming to stop,repaired front wheel speed sensors first to stop pulsing at stops.rear shoes were into rivets,both rear cylinders leaking,right e-brake cable stuck right front calipe...		 View
2001 GMC Sierra 5.3L 2-3 shift
Vehicle hangs up in 2nd, This is the part that has me baffled, On a test drive at about 1/4 throttle vehicle does not shift into 3rd, RPMs go up and there is nothing there basically, but if you manually select 2nd and get the vehicle above about 50 MPH and the...		 View
1997 Oldsmobile Aurora 4.0L radio
i am having problems with the radio when i get out of this car and shut the door the radio shuts off and interior lights come on and when the interior lights go off the radio comes on and the antenna goes up and doesnt shut off till i open the door. no matter ...		 View
2004 Saturn Ion 2 2.2L clutch hydraulics
this one is driving us crazy, the clutch wont bleed out but were having a problem finding the bleed port according to the dealer theres a 9mm bleeder screw some where on the slave/hydrualic line. we see a nipple with a rubber cap on the slave cyl but it doesnt...		 View

Fixes & Summaries for GM
Fix/Summary Answers
2002 Buick Rendezvous 3.4L wiper
Change the wiper motor and wiper switch. every thing works.thank for for your help Christ,Michal,David.all other help from IATN members.		 3
1993 Chevrolet Van 5.7L Excessive Emissions, Poor Idle Quality, Hesitation, Cuts out, Misfire
Thanks a bunch to everyone who responded! I wasnt able to check this over the weekend and one of the other guys stayed late friday to work on it. He did figure it out and Matt [...] you were right! Throttle body was all gunked up. Thanks again!!		 15
1999 Chevrolet Suburban 5.7L fuel gage
well still not fixed im out of ideas i would like to try a ecu but thats a lot of money if it dont work like i said befor its the 2 fuel pump assy and the consern didnt change 		3
2000 Chevrolet Tracker 2.0L Poor Idle Quality, Cuts out, Stall, MIL Lamp on
Thankyou for all replies recieved. We were finally able to locate a used Pcm with matching #s. Installed and vehicle ran well. The customer has been on the road for two weeks- no problems. Thankyou again.		 3
2001 Chevrolet Impala 3.8L Starter
Thanks to all who replied. Several of you said that a starter would fix the problem. So far it has. I have had a new one on it for three days now and so far so good. Usaully I could get it to act up by now. I think this one is finished finally. Thanks again to...		 26
2004 Chevrolet Silverado 5.3L Engine
Okay, Finally got back to her. At first I thought their was a lack of oil, turns out I just needed it to run longer. Oil was where it needed to be. But I still have the tick, rattle, knock. Removed valve covers again and did the old hold the rocker arm whi...		 9
2007 Chevrolet Avalanche 5.3L TPMS& remote
the latest software for TIS 2000 was the answer to this problem getting everything up to date seems more important that ever to day.after programing the RCDLR off it went		 11
1995 Geo Prizm 1.8L No Start, Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire
Many of you replied and confirmed my suspision about a weak coil. I replaced the Distributor with an OE part (coil is inside), and fixed the car! Much thanx for all replies. Have a good week all. Adam [...] (Longs Garage, Urbana, Illinois)		 6
2000 GMC Pickup 6.5L Fuel filter.
Thanks to all who responded to our help request. Special thanks to Brent [...] for you detailed response. We replaced the MFI Pump, Injectors, Lift Pump and the Injectors. We also dropped the fuel tank and cleaned the entire fuel system. Seems to be good to ...		 7
2002 Pontiac Firebird 3.8L MIL Lamp on
After telling the customer about the OEM converter that all of you talked about he has decided to carry to the dealer for a reprogram first Alldata suggested that before installing new OEM converter. Thank you for all your help. Trouble codes: P0420 (cat ineffeincy).		 10
2005 Pontiac Grand Prix 3.8L Surge,
THE SECOND PCM WE ABLE TO PROGRAM. THE ONLY THING I THICK OF IS THE BATTARY VOLTAGE WAS DROPING TO LOW AND LOCKING THE PCM UP. THE SECOND PCM WAS CONNECTED STRAT TO THE PC AT THE DEALSHIP. ALL IS GOOD. NOW CAR WILL START AND RUN. AFTER ALL OF THIS THE CAR STIL...		 3
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