GM Automotive Technicians Technical Discussion and Fixes for Apr 7, 2010

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Open Help Requests for GM

	Help Request	Answers
	1991 Cadillac DeVille 4.9L 1st gear VIN: 1G6CD5385M this car takes off in second gear & shifts up ok.reverse is good w/power,checked all fuses and ok but one 15 amp #5 location on very bottom on pass side lower of left fuse panel is all on fuses panel that blow instantly,goes to windshield washer pump.looking f...	View
	1984 Chevrolet El Camino Conquista 5.0L blower motor VIN: 1GCCW80H5E this el camino has blower motor operation in all three speeds except for high speed. we have replaced the blower resistor and the blower motor relay. my electrical diagram off of all data shows that on high speed there is an orange wire from the control switch...	View
	1991 Chevrolet S10 4.3L Poor Idle Quality, Hesitation, Surge, Poor Fuel Economy VIN: 1GCCT14Z4M Ok, This is a friends truck who is going through a Divorce. At first he bought it to just 4x4 it but now he has to have it as a daily driver. Upon initial inspection you can tell it's Running Really Rich and it seems that the timing is Retarded. He Replaced th...	View
	1992 Chevrolet Corvette 5.7L speedometer VIN: 1G1YY23PN2 vehicle came in with no speedo operation but display does cone on and displays an sys message. i do not have much exp with vettes.have followed communication test from mitchell and cannot complete due to the fact that te radio control head is gone cust says wo...	View
	1994 Chevrolet Camaro Z28 5.7L evap temp sensor VIN: 2G1FP22P9R This one came in for ac inop, recharged system, now full and still ecm refuses to supply ground for the relay. Presure switch reads 48#s evap temp sensor is sending a 1.76 volt signal to ecm. Thats my question what should this reading be? Found one post in arc...	View
	1994 Chevrolet Camaro 3.4L clutch VIN: 2G1FP22S4R have a clutch job that has gone really bad on me!!! car was towed in for no clutch. after checking car out determinted it needed a clutch. have installed new clutch, new slave and master clyinder, resurfaced fly wheel.. probolem is that the clutch will not ful...	View
	1996 Chevrolet S10 2.2L Stall VIN: 1GCCS14477 Customer brought the truck in with the complaint that intermittently the truck will die and all the gauges will zero out. Then it will then crank and not start and the gauges remain off, finally it will start and gauges will work again until the next episode. ... Trouble codes: P0141 (HO2 Curcuit fault)	View
	2001 Chevrolet Blazer Trailblazer 4.3L MIL Lamp on VIN: S122109015 customer said truck would over heat some times,but the check engine light stays on,the reduced engine power light is on also,i cleared codes,[...] reduce engine power light come back on as soon as i got a mile up the road,p1481 did not come back on but truc... Trouble codes: P1481, P1484	View
	2001 Chevrolet Silverado 1500 4.8L Poor Idle Quality, Stall VIN: 2GCEC19V31 this truck idles to low ,around 500,even with a/c on and stalls on low speed turns. vehicle has no other driveability issues and runs great otherwise.thank you for any future help.	View
	2002 Chevrolet Trailblazer LTZ 4.2L power windows VIN: 1GNDS13S82 when acting up veh, all functions on window switch panel fail(windows, seat heater) usually has problem present when begin checkout but starts working after 20-30 min, im posting this for another tech, so if there are any questions or more info is needed, ask,...	View
	2002 Chevrolet Silverado 2500 HD 6.6L Hesitation, MIL Lamp on, erattic shifting VIN: 1GCHK23142 Thanks in advance; initial complaint was due to erratic trans shifting, cluster issues, and door locks. tried to scan vehicle, and it wouldn't communicate. if you put the ignition switch not quite to the run mode then it would. replaced switch, same problem. i... Trouble codes: U1301 (class 2 data high voltge)	View
	2003 Chevrolet Tracker ZR2 2.5L MIL Lamp on VIN: 2CNBJ73453 Tonight I found that I had Battery current coming from the Heated oxegen sensor relay at the blue wire which goes to each of the four sensors. The problem is I have approximatly 5 volts at blue wire at the connector for o2 sensor bank 2 sensor 1. Is there a co... Trouble codes: 161B (155 -), 155 (141b -), 141B (135b -), 135B	View
	2004 Chevrolet Silverado 3500 6.0L Misfire, MIL Lamp on VIN: 1GBJC39U24 Hi Folks! Ok truck came in missfiring on #2 and #7 cylinders. Checked for spark and fuel and injector pulse...all good! Put in new plugs wires and 2 coils...still missfires 2 and 7. Checked compression on 2,7 and 1 all 165 to 170 lbs. did leak down test on 2 a... Trouble codes: P0302, P0307	View
	2004 Chevrolet Silverado 3500 WT 6.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1GBJC34U84 hi all, truck came in with misfire code, hooked up tech2 pulled po300, checked misfire monitor, miss on #s 3-4, pulled plugs on those cylinders, they are new no cracks. check for vacuum leaks with carb cleaner none found.switched wires,coils,plugs,injectors, m... Trouble codes: P0300	View
	2005 Chevrolet Trailblazer LS 4.2L Poor Idle Quality, MIL Lamp on VIN: 1GNDT13S15 As usual, the P0410 code set due to AIR control solenoid rusted. The question I have is & research has not produced the answer is this: if the AIR control solenoid shorts, will it casue an erratic idle (P0300- scanner showing random missfires on all cylinders)... Trouble codes: P0300 (Random Miss), P0410 (Secondary Air), P0622 (Gen F control)	View
	2005 Chevrolet Cobalt 2.2L Surge, MIL Lamp on, Hard shifts VIN: 1G1AK52F35 This cobalt is really becoming a pain. The first time this car acted up, The complaint was the transmission started shifting hard, gauges acted erratic, steering got stiff and multible lights lit up to include traction control and ABS. Also the shifter interlo... Trouble codes: U2100 (CAN communication error)	View
	2005 Chevrolet Silverado 2500 HD LS 6.6L Speedo VIN: 1GCHK23295 This vehicle actually has 2 problems. Customer states that his speedo made some clicky noises then started reading wrong. When I got the truck the speedo was already at 32. I drove it and that's where the needle starts to move. I followed someone doing 35 and ...	View
	2005 Chevrolet Impala LS 3.8L speedometer VIN: 2B1WF55E45 I am about to release this nightmare to the dealer unless I can figure out where to go from here. The glitch is very fast and happens at 40 to 50 mphs.	View
	2007 Chevrolet Trailblazer LS 4.2L sir system VIN: 1GNDT13SO7 To the best of my knowledge, SIR light was off prior to my service with the ign. switch.I rechecked all of my work and cannot see an error.I pulled in another GM car with same harness and did a comparative analysis. The resistance readings are the same. 2ohms....	View
	2007 Chevrolet Silverado 2500 HD Classic WT 6.0L 1-2 shift VIN: 1GCHK24U77 this truck is very intermintant. the customer states it is worse first thing in the morning. i have only got it to act up once on me. what it acts like to me is when it shifts out of first it goes into neutral then slams into second. most of the time this truc...	View
	2009 Chevrolet Impala LT 3.5L Housing VIN: 2G1WB57K39 Cooling fan housing was cracked when driver fell asleep and drove into a hwy pole, which snapped off and smashed the roof and trunk. I have the body work all done, and bought a new GM dual motor cooling fan housing, to replace the original broken unit. The pro...	View
	1996 GMC Jimmy SLE 4.3L start VIN: 1GKDTY13W8 erratic dying, no restart. customer complained of stalling and dying. noticed volt gauge when key is on reads 13.8 volts, car start and ran ok. after driving for 10 minutes voltage starts to drop to about 13.4 ,if ac is turned on, voltage drops to about 9 volt...	View
	1997 GMC Yukon SL 5.7L Hesitation, Surge, Cuts out VIN: 1GKEK13R7V Hesitates and surges under load as if it had a turn signal flasher on the injectors. ECM data shows bank 1 at 0.0 ms, bank 2 at 15.3ms. I have verified this with a scope, I get a flat line at battery voltage, when the problem occurs. I have checked resistance ...	View
	1997 GMC K1500 Sierra SL 5.7L booster VIN: 1GTEK14R8V the brakes work great in this truck, they stop normally and feel great, they have normal wear and all is fine no issues on all four corners.but when you perform a panic stop the pedal is really really stiff for a few seconds then abs takes over. but the issue ...	View
	2002 GMC Sierra 2500 HD 6.6L Cooling Systems VIN: 1GTHK29172 We are looking for the source of a coolant leak on this duramax. The leak is coming from the left rear of the engine and first appeared to be coming from what looks like a block plug behind the oil filter. after drying and looking closer, there is a trail of c...	View
	2005 GMC Envoy XL SLE 4.2L engine VIN: 1GKET16S15 hi techs. this vehicle uses excessive oil, 1 litre to 500-600 km. it doesnt smoke blue, or run poorly.customer just bought it one month ago. checked pcv system appears ok. i have not did a wet dry compression test yet. has this engine been a problem. i know th...	View
	2001 Pontiac Grand Am SE 3.4L engine VIN: 1G2NF52E91 Hey Guys, IT KEEPS BOILING COOLANT OUT THE OVERFLOW TANK, @219 DEGREES FANS COME AT 225 LOW SPEED 232 HIGH SPEED , REPLACE CAP DOES ANYBODY HAVE ANY IDEAS , IT PASS THE BLOCK TEST AND DOES NOT OVERHEAT..	View
	2001 Pontiac Aztek 3.4L cluster VIN: 3G7DA03E61 whats going on is the gauges drop out and then come back and the dash light flash off and on. its not all the time, seam to happen more under a load and when it starts its off and on every 2 seconds. tested battery ok, check charging systen ok 14.2 volts, chec...	View
	2003 Saturn Vue 3.0L MIL Lamp on VIN: 1S24D25S22 Hey guys I've got this vue that i removed the upper intake and repaired a coolant leak at the oil cooler. After repair as soon as the key is turned on the check engine light comes on and stores a PO700 trans. code. test driving the vehicle is fine no problems ... Trouble codes: P0700	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	1986 Chevrolet K5 Blazer Custom 6.2L starter VIN: 1G8ED18J7G We purchased an AC Delco starter & set it up according to the instructions using a 1/8 drill bit between the the flywheel & drive. All is well, thanks for the replies, almost everbody responding hit the nail on the head (rather than the thumb:) what a great w...	14
	1994 Chevrolet K3500 6.5L Hesitation, Stall, MIL Lamp on VIN: 1GBGK24F8R well guys i do thank all of you for the valuable help that was submited. i cannot call this one fixed as of yet becouse we are waiting on aprovial from the military unit that this truck belongs to. after replacing a worn timing chain, and a un timable pump ... Trouble codes: 88 (tdc relearn error).	12
	1995 Chevrolet K1500 Silverado 5.7L transfer case VIN: 1GTEK14KXS THANKS TO EVERYONE WHO REPLIED. ALL MOST ENERYONE SUGGESTED ROLLOUT OF TIRES. UNKNOWN TO ME AT THE TIME WAS THAT THE CUSTOMER PUT ON THE SPARE THAT HAD NEVER BEEN RUN BEFORE. THIS TIRE CAUSED TO ROLLOUT OF THE TIRE TO BE ALMOST 1/4 OF A TURN LESS THEN THE OTHE...	24
	1998 Chevrolet C1500 Silverado 4.3L No Start VIN: 1GCEC17W1W Sorry for the delay thanks everyone it was the aftermarket timing cover that was keeping the vehicle from starting!! Trouble codes: P0339.	13
	1987 GMC R1500 5.7L Poor Idle Quality, Stall, high idle dies in ge VIN: 1GTGV24K1H replaceing distrib has indeed cured the prob ...thank you so much for the help	26
	2001 GMC Sonoma SL 4.3L Hesitation, Stall, MIL Lamp on VIN: 1GTD19WX1K Well this was a complete nightmare, remember this only happened on heavy accel. at about 65 mph or higher. The cat was partially plugged and melting when I cut it apart, but that did not fix it. The MAF was new and the fuel pump was 1 year old and good pressu... Trouble codes: P1010, P0300.	27
	2003 GMC C4500 Topkick C4C042 6.6L speedometer VIN: 1GDE4E1163 Well we have this thing fixed. We took a the PCM out of this truck and put it in a identical working truck and that truck was doing the same thing. So we ordered a used PCM because a new one is $1000.00. Programmed it and the truck did the same thing. During p...	6
	1997 Oldsmobile Cutlass Supreme SL 3.1L Misfire VIN: 1GH52MXVF3 Well I pulled the valve cover and sure enough the #1 exhaust rocker arm laying on it's side, pulled clean out of the head. I repaired it with a heli coil and it's back in the wind again. Sometimes it just takes a new set of eyes to solve the problem. Thanks ... Trouble codes: P0300.	18
	2004 Saturn Ion-1 2.2L door locks horn VIN: 1G8AZ52F24 customer took the vehicle and has not returned and I have not heard back from her. so I will close this post with no fix. I will be sure to repost when and if i get the car back for info purposes. thanks for the replies.	4
	2006 Saturn Ion-3 2.4L ignition swicth VIN: 1G8A155B36 Yes those who have this issue will have to replace the ignition cylinder and key. I would probably do the switch at the same time too. Thanks	4

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