GM Automotive Technicians Technical Discussion and Fixes for Apr 30, 2009

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Open Help Requests for GM

	Help Request	Answers
	1993 Cadillac DeVille 4.9L Excessive Emissions VIN: 1G6CT53B7P My forehead is sore from beating against the wall... This should have been cut and dry (right??) The Code 52 for "Memory Reset" can be caused by changing the battery, a dead battery, loss of power to the ECM (an ignition feed going open for example) or ECM/Pr... Trouble codes: 52 (Memory Reset)	View
	1998 Cadillac Seville STS 4.6L Cuts out VIN: 1G6KY5497W My question is will this cut off fuel at 90mph? I remember order unit you can replace with non air type but on this one through dealer is not allowed. Is their a after market kit which will fool the computer?	View
	2004 Cadillac DeVille DHS 4.6L all power windows VIN: 1G6KE57Y34 Hello group,this Cadillac is kicking me around some.I`ll start off by saying this problem is and has been intermittent for at least four mounths.My first contact with it four mounths ago was an inoperative power window on the drivers door.the window was down a...	View
	1994 Chevrolet K2500 5.7L stuck in 3rd gear VIN: 1GCFK24K2R I have this 94 truck that is kicking my rear. It is stuck in 3rd gear, it has reverse, and manual second. I have checked the shift solenoids, checked for power at the pink wire at trans, replace ignition switch, and replaced the pcm. The condition has not chan...	View
	1995 Chevrolet G20 Chevy Van 5.7L 9 port vacuum mode switch VIN: 1GBEG2SK8S Some of the ports on the 9 port vacuum control switch are eaten away causing air flow to stay on the floor no matter where the mode lever is set. The ports look almost like they have been sand blasted off. We have replaced this part many times on this vehicle,...	View
	1995 Chevrolet Astro 4.3L Excessive Emissions, NO CLOSED LOOP VIN: IGNDM19W6S vehicle failed NOX testing at emmisions. will not go into closed loop. o2 sensor reads .675-.750 at idle steadily (not switching) and at cruise will read 40mv or less. replaced o2 sensor and have same readings. no vacuum leaks were found (smoke tested) fuel pr...	View
	1997 Chevrolet Camaro Z28 5.7L Clutch VIN: 2G1FP32P5V i hope someone can help me, my customer just bought this car in arizona & drove back to south dakota. on the way home approximatly 150 miles into the trip he started hearing a buzzing or whirring noise coming from somewhere in the shifter area. if he shut the ...	View
	1998 Chevrolet S10 2.2L abs VIN: 1GCCS1440W This customer has had this problem for about 4 years. (I just started working on this problem) After a rain the first stop the abs will activate at low speed. It will not do it again the rest of the day. All the brakes have been replaced as well as the rear sp...	View
	2001 Chevrolet Cavalier LS 2.2L wont set readiness VIN: 1G1JF52441 We have this 2001 Cavalier that wont set the final 2 readiness flags. The catalyst and the Fuel Evap. it has no codes or history codes, closed loop, temp is normal, both o2 sensors look normal, however my otc genysis says the twc temp is over 1000 degrees whe...	View
	2002 Chevrolet Trailblazer LS 4.2L No Start VIN: 1GNDS13S02 This TB has an intermittent no start after brief shut down. You can drive to the Post Office, go in and do your business, when you come out it may not start. I can hold the accelerator to the floor, like a clear flood, and it will start. Puffs smoke out of tai...	View
	2003 Chevrolet Silverado 3500 LS 6.6L cluster VIN: 1GBJK39113 vehicles dash lights flicker and radio pops when the clutch pedal is pressed.i have search for any wiring issues and found nothing .no harness rubbing or shorted .i hope someone may have seen this before. thank you	View
	2004 Chevrolet Silverado 2500 HD 6.6L speedometer VIN: 1GCHK29144 Hello fellow techs. I need some help with this one. It is starting to get me. The customer brought the vehicle in complaining that the speedometer was reading incorrectly. Customer stated that speedometer will read 80 and gps will show 72-73 mph. I have compar...	View
	2004 Chevrolet Silverado 2500 HD 6.6L MIL Lamp on VIN: 1GCHK23104 this vehicle came in with a check engine light on. the glow plugs are operating fine and its strarting fine. the signal circuit from the relay to the pcm has 1.3 volts with the key on and the glow plugs off...it should be less than .02 volts. with the relay un... Trouble codes: P0380 (glow plug relay ciurcuit)	View
	2005 Chevrolet Silverado 2500 HD 6.6L Cuts out, Stall, MIL Lamp on VIN: 1GCHK23235 Hello everyone, I need help with a chevy diesel. We have three codes stored, PO335, PO341, PO0016. Do not have much time working with newer diesel engine's. We have replaced the cam and crank sensor's. Have checked the reluctor wheel as best we can for the cra... Trouble codes: P0335, P0341, P0016	View
	2005 Chevrolet Trailblazer LS 4.2L MIL Lamp on VIN: 1GNDT13S55 customer came in with p0410 secondary air injection and stated he had an air pump installed. when i checked it out i found that return hose going to the air valve had blowen off the air pump turned out the plastic fitting was no good replaced it cleared code a... Trouble codes: P0410	View
	2006 Chevrolet Malibu Maxx LT 3.5L Steering VIN: 1G1ZT63856 Hello fellow techs. I have a 2006 malibu max that inter. sets a c0545 trouble code steering Torgue sensor fault. Light on dash says service steering and steering asist is gone. Have performed a steering wheel position relurn and a torgue relurn with Tech 2 no ...	View
	1997 GMC K1500 Sierra SL 5.7L failed emissions VIN: 2GTEK19R4V Failed emissions due to O2 sensor not monitored. Tested with multible scanners and all display "Oxygen sensor not supported" The scanners show the sensor activity and this was confirmed by testing inputs to pcm at pcm. DNR told them to replace the pcm and was ...	View
	1998 GMC Savana 3500 5.7L Cuts out VIN: 1GCHG35RXW There is no problem found anywhere but this van continues to miss at cruise only. It's the second GM truck i've had with this problem and am unable to find the problem. Everything I can think of that would cause a stumbling at cruise I've replaced. thank you.	View
	1999 GMC C1500 Sierra SL 5.7L distributer VIN: 1GAS452LAS hello fellow techs & thanks in advance... i replaced intake gaskets due to oil and water mixed... everything came out great except for one thing ... po13??(i dont recall)something about manufactor ign.. read ALL DATA it said dist. installed wrong... the 350 st...	View
	1997 Pontiac Grand Am GT 2.4L Starting VIN: 1G2NW52T3V Intermittently car will not start, customer leaves vehicle for a short while then it will start again. I have not been able to verify but I have retrievd a code P1629 which is with the anti theft. I have checked for any broken wires for the passlock sensor non...	View
	2000 Saturn SL2 1.9L shifting VIN: IG8ZM8289Y this trans shifts hard into the gears. we have replaced valve body twice. the last time valve body was replaced it worked good for a day or so then came back with the same harsh shifting problem. also tried new computer but still same problem. anybody run acro...	View
	2003 Saturn Ion-3 2.2L passlock VIN: 1G8AL52F13 customer had the car towed in due to a key cly that would not rotate, Had a new tumbler coded with key from the dealer and proceeded to drill 2 holes in the housing to push on the tumbler detents, had to drill a 3rd hole to push the tumbler lock bar in so i co...	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	1954 Buick special 325CID missing vacuum lines VIN: 4NOTAVILAB ok guys i think we got this one nailed,i want to thank Bill [...] for scanning and sending the diagram,i'm glad he has such an extensive library,and i could'nt have done the repair without IATN either,as usuall you guys came through again,thanks to all,Jim Oake...	14
	1991 Cadillac Allante 4.5L 4 analog gauges VIN: 1G6VS3384M Ok so i had to step back from this a little...The gauges work key on engine of, which tells me that the BCM is working properly. i just seem to get "noise" on the data line when the engine is running. I checked the data line from the BCM to the gauges and foun...	3
	1999 Cadillac DeVille 4.6L Steering Wheel VIN: 1G6KD54Y9X Thanks For All The Help,Sorry It Took So Long To Close This Help Request.I Suggested Replacing The Rack To Customer He Is Still Not Sure If He Wants To Put Money Into Vehicle For This Problem.Because Other Than The Steering Wheel Moving While Sitting Still The...	10
	1994 Chevrolet C1500 Suburban 5.7L Excessive Emissions VIN: 1GEKEC16K6 ok its fixed, i liked and tried the idea of the brake cable to unplug the egr ports. well this one was so plugged there was no way it was going to happen on the truck. we removed it and unplugged it, wow guys this one was really plugged up i did use the cable ...	11
	1997 Chevrolet C3500 Cheyenne 7.4L No Start VIN: 1GCHC33J2V I thank every one that send the replies .I did a fuel leak down test on the injectors found 5 injector leaking.I replace all of them. now the engine start.I had too remove the blenum to see the injector leaking slowly on 5 injector.now the engine starts in one...	12
	1998 Chevrolet Malibu 2.4L Excessive Emissions, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire VIN: 1G1ND52T8W Well after several great recommendations. I proceeded with more testing. I performed an injector noid test to verify all injectors were working electronically. I noticed when I had #1 and #4 injector unplugged, it made no difference in how the engine ran. So I...	9
	2000 Chevrolet Astro 4.3L steering VIN: 1GNDM19W8Y THIS NOISE SEEMS TO COME FOR STEERING COLUMN .MABYE A BEARING OR CLOCKSPRING .MY CUSTOMER DECLINED ANY FURTHER DIAG FOR NOW UNLESS IT GETS WORSE. THANKS TO ALL FOR YOUR HELP	5
	2002 Chevrolet Trailblazer LS 4.2L Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1GNDT13542 The vehichle seems to be fix at the moment. I ended up cleanning the grounds on the driverside frame. Which was very dirty. All weird problems have disappeared. Talked with the customer, and he said it's running good with NO problems. All of you have been ... Trouble codes: B0017, U, 1000 (Class 2 serial comm problem).	4
	2005 Chevrolet Colorado Z85 LS 3.5L crankshaft VIN: 1GCDT13615 Sorry for not posting this sooner, but customer informed me he has an extended warranty from dealer where he purchased truck, He promised me he would let me know what they do mto fix it but I have yet to hear from him, Thanks for the replies anyhow. Matt	6
	2008 Chevrolet Impala LT 3.9L engine VIN: 2G1WC58388 OK GUY'S LOOKS LIKE THE ENGINE NEEDS TARE DOWN ,TO FIND THE CAUES OF THE NOISE , CUSTOMER DECLIND AT THIS TIM [...] ,THANK YOU FOR YOUR HELP .	19
	1999 GMC Savana 2500 5.7L No Start, Hesitation, Cuts out, Stall VIN: 1GTFG25R7X thanks to everybody that took their time to reply, got some helpful suggestions from you guys out there. the van was acting up due to low fuel pressure, unfortunatly it was hard to get to act up so I had customer drive it with fuel gauge. the pressure dropped ...	17
	2006 Hummer H3 3.5L Starting VIN: 5GTDN13636 Thank you all for your replies, i let the car sit for a few days in the sun, with the fuse box conectors disconected, and the battery also disconnected to dry out the engine bay, roughly 3 days later, i went to connect everything back together, and whent to st...	5
	1995 Oldsmobile 98 Regency Elite 3.8L Cuts out, Stall VIN: 1G3X52K4S4 thansk for all the good info group, i found a correct size mateing terminal and grip checked all the pins on all three ecm connectors, i checked the batt feeds "two" into the pcm with a large amp test light(fog lamp bulb)and one ign switch feed also. with same...	15
	2004 Oldsmobile Silhouette Premiere 3.4L evap core VIN: 1GHDX13E34 Thanks for all replies We removed the evap core yesterday - the core was not leaking. What we found was one of the seals between the expansion valve and the evap core was leaking. The seal had a inperfection in it that you could see.Was bad new or damaged w/in...	4
	2000 Pontiac Firebird Formula 5.7L No Start VIN: 2G2FV22G3Y Thanks to all the help, after re-checking system removed crank sensor and used a flexible inspection scope. Some of you asked this is a coil over plug ing. system. After using inspection scope could see damage to reluctor wheel, also still had some of the old ...	24
	2003 Pontiac Grand Prix GT 3.8L Cuts out, Stall VIN: 2G2WS52274 We are calling this one fixed. Thanks to all of the replies we recieved. We replaced the crankshaft position sensor and scrubbed the throttle body clean with Mopar combustion chamber cleaner and a toothbrush. We've been running this car all over in the past we...	11
	2006 Pontiac G6 GTP 3.9L Replaced BCM VIN: 1G2ZM55166 Thanks for all the help guys. The used car dealer finally got a new bcm and I programed it yesterday with my tech 2, didn't have to do any downloads or anything with a computer subscription. That was my original concern. Thanks again.	11
	2001 Saturn SC2 1.9L MIL Lamp on VIN: 1G8ZY14761 Thank You for all the replies. 5 replies said to replace the module. We replace module and retested all is well car fixed. Trouble codes: P0341.	9

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