GM Automotive Technicians Technical Discussion and Fixes for Jan 11, 2012

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Open Help Requests for GM

	Help Request	Answers
	2005 Buick Century Custom 3.1L Guages VIN: 2G4WS52J55 Hi and thanks for your info. This car has the dash brake light on (Fluid is full & Park brake is off), The gas guage reads 1/2 all the time, the temp guage is not working properly and the parking indicator doesn't change all the time. On the older models the I...	View
	1996 Cadillac Fleetwood 5.7L throttle VIN: 1G6DW52P6T this old cadillac is in very good condition except for the fact that it's limited at 76m.p.h.. At that speed the gaz pedal pushes up on your foot so i'm assuming that the traction control unit is working but why is it? No history on anything unusual before it ...	View
	2000 Cadillac DeVille DHS 4.6L Dash/cluster/HVAC display VIN: 1G6KE57Y3Y I do have communication with DIM,IPM AND IPC. Data shows good on dim & ipm but on ipc scan data shows no data on all values. This thing is eating my lunch. Any or all advise greatly apearicated... (-:	View
	1995 Chevrolet Blazer 4.3L No Start VIN: 1GNDT13W5S This blazer will not start unless a jump or a battery charger is hooked up. When you turn the key on you can hear the fuel pump run and the engine does try to start. If you hookup a charger to it the fuel pump sounds stronger and it will start right away and r...	View
	1998 Chevrolet Malibu LS 3.1L Starter VIN: 1G1NE52M0W This Malibu came in on a hook due to a no start condition. Customer went to work and at the end of the day the car didn't start. Turn the key and you just get a click from the starter. Thought, Easy, new starter. Put one in and still same thing! Weird thing is...	View
	1999 Chevrolet C2500 5.7L Rear Brakes VIN: 1GBGC24R8X Rear Brakes are locking up sometimes more so when hot. Possible Combo/Proportioning valve but no way to test it and a new one is expensive although works fine when cold. No brake codes and system is properly blead. This is the Master vac. assisted type (not th...	View
	2000 Chevrolet Express 2500 5.7L fuel pressure VIN: 1GCGG25R3Y customer brought this van in complaints of hard start. he said to tune it up. it ran fine so i couldnt test anything. so doing what customer wanted i tuned it up. only to find the problem is fuel pressure. it ran fine for a few minutes then it did what he said...	View
	2001 Chevrolet Express 3500 5.7L turn signals VIN: 1GCHG39RX1 Thanks in advance for any help. This truck came in with the complaint of when the turn signals are on whether it be left or right it looks as if the flashers are on. On my diagnostics i have found that it only occurs with the headlamps on. I have tried new fla...	View
	2001 Chevrolet Blazer LS 4.3L ses light VIN: 1GNDT13W81 ok i have a tough on here need help...replaced fuel pressure sensor, pcm an wire from pcm to fps... still getting P1639 5v refernce 2...not sure what else to look for here unless there is something im missing any help or leads would be great	View
	2005 Chevrolet Trailblazer LS 4.2L blower VIN: 1GNET16S35 First this vehicle came in with no blower at all, then I replaced the resisitor and blower started to blow. But this vehicle sometimes won't blow at all. it is intermittent, no matter what setting I place the sysytem in. It is automoatic and can be placed dire...	View
	2005 Chevrolet Aveo LS 1.6L MIL Lamp on, "hold" lamp VIN: KL1TD52665 Hello Group, Thanks in advance for your time and efforts! As noted, this Aveo exhibits an intermittent p0300 always. No misfire counters on my Tech 2, no driveability issues and cannot feel a misfire. The real problem for my post involves the "hold" lamp that... Trouble codes: P0300 (Random cylinder misfire), U0401 (Invalid data recieved from ecm)	View
	2005 Chevrolet Silverado 1500 HD LS 6.0L Encoder Motor VIN: 1GCGK13U35 Hi every one. The vehicle came to us with Service 4WD message and code C0327-Encoder Motor circuit. Customer has had 6 motors replaced without fixing problem.(go figure) We rebuilt this NVG246 transfer case because the shift shaft had excessive play in it. All...	View
	2006 Chevrolet Express 2500 6.6L Poor Idle Quality, noise/vibration VIN: 1GCGG292X6 This Duramax has a loud noise, sounds like exhaust leak, but not a single cylinder, sounds uniform like after turbo. Also has knocking noise and vibration which seems to come from the turbo. We removed the exhaust pipes that feed into the turbo and that correc...	View
	2008 Chevrolet HHR LS 2.2L Power locks Shift interlock VIN: 3GNCA13D38 After sitting for at least eight hours when the car is started the door locks unlock and continue to unlock for five minutes. Also the shift interlock solonioid releases at the same time with foot on brake pedal or not. What I mean by that is that the door unl...	View
	2009 Chevrolet Malibu LT 2.4L Electronic VIN: 1G1ZJ57B29 We have this Malibu with code c0131. tried cleaning connections at bcm as per gm bulletin, but code reappears in a few days. Customer has had no problems with brake lights as far as we know. Procedure says to replace BPMV first then if still comes on to replac...	View
	2010 Chevrolet Equinox LT 2.4L MIL Lamp on VIN: 2CNALDEW9A CODE PO172, TRUCK RUNS GOOD, NO PROBLEMS. ENGINE DATA IS CONSISTENT WITH FREEZE FRAME. I can only run OBDII scanner. everything is hooked up properly. If I disconnest PCV hose to air box after MAF the ltft goes to -10.0%. Both O2 s are working. Thanks for any ... Trouble codes: P0172	View
	2001 GMC Sierra 1500 SL 4.3L engine runs very rough replaced intake gaskets duo VIN: 1GTEC14W61 after all that truck will not run properly rough idle exhaust manifold glowinfg red hot started on passenger side cut cats off then red hot moved to drivers side all started with radiator jug full of black slimey sludge due to leakage of oil into cooling syste...	View
	2002 Oldsmobile Intrigue GX 3.5L c0040 VIN: 1G3WH52H92 Car came in with ABS light on and Code C0035, checked left front senor... On inspection, something had gotten in axle, replaced axle, wheel bearing and abs wiring harness, after work was completed got code c0040, right sensor, everything seems fine on the righ...	View
	2003 Oldsmobile Alero GL 3.4L Excessive Emissions, Hesitation, Surge, Cuts out, Misfire, Poor Fuel Economy VIN: 1G3NL52E73 This vehicle just suddenly started running very bad under accel and smelling bad out the tail pipe and would hardly pull when accelerating hard. Very similar to a clogged cat. Checked back pressure - less than 1 psi! Had no check engine light and had only one ...	View
	2009 Pontiac G5 2.2L fuel pump VIN: 1G2AS58H39 I can activate pump using scan tool. If I cycle 5-6 times, car will run for a few seconds. In the process of checking the bodyshop work, I noticed the RR tail,marker,& reverse light,trunk light are dim like a ground issue. I have checked for pinched/broken wir...	View
	2002 Saturn Vue 3.0L Drive-axles VIN: 5GZCZ63B72 I need some imput from all the Saturn techs out there. This Vue will lock the rear wheels up at times, speed doesn't matter. When this happens you can back the vehicle up, but not move forward. It will also happen to only the left rear at times. I disabled the...	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	2002 Buick Rendezvous CX 3.4L Cooling Systems VIN: 3G5DB03E82 ty for all the responses.. yupp the rad cap did fix this problem. guess i was overthinking the whole situation sinve I did so much other work to the vehicle and forgot the simple things.. ty again	32
	1998 Chevrolet K1500 Silverado 5.7L front axle I want to thank eveybody for ther insite.we pulled it apart and replaced the seal with the updated gm part,bearing and axle looked ok.Made my son do all the grunt work as he's the one who want's to go mudding.Well I guess that we will have to wait and see when...	17
	2000 Chevrolet Tahoe Z71 5.7L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1GNEK13R8Y At first we only did one compression test on the entire engine, and that was at first. Went back and retested all cylinders and found that cylinders 6 had 60psi and 8 had 0psi. These cylinders were showing no misfire on the misfire monitor, only 5&7. remove... Trouble codes: P0300.	51
	2006 Chevrolet Silverado 1500 LT 5.3L Misfire, MIL Lamp on VIN: 3GCEC14Z76 Thank you for all the help! We replaced the bank2#2 o2 sensor and the values returned to normal. The backpressure test and tps sweep came up normal. We did not find any cold weather vacuum leaks. The fact that the failure record data was a result of the mis... Trouble codes: P0300.	5
	2003 GMC Savana 3500 6.0L Cuts out, MIL Lamp on VIN: 1GDHG31U33 thanks again for all the input and help this one is fixed, decided to test the maf sensor a little more, i back probed #5 wire yellow wire on maf with multimeter on hz setting, had 3.2 hz at idle when warm but instead of steady increasing when reving up motor ... Trouble codes: P0171, P0174, P0154, P0158, P0131, P0134.	12
	2005 GMC Canyon Z71 SLE 3.5L accessories VIN: 1GTDT13635 After asking the customer numerous times if there were any aftermarket products installed in the vehicle and him answering no, I found a periphial HD radio unit installed in a pigtail for the radio. This product is intended to allow the customer to utilize the...	11
	2001 Oldsmobile Silhouette Premiere 3.4L Cooling Fan VIN: 1GHDX23E31 HI; EVERYONE. THANKS A LOT TO ALL YOU TECH. WHICH TAKE YOUR TIME TO HELP ME, THE PROBLEM WAS ECM , IT COULDN`T GROUND THE HIGH SPEED RELAY. THANKS AGAIN MATT	12
	2003 Pontiac Montana 3.4L Starter Circuit VIN: 1GMDX03E33 I suspect a bad connector at the relay. We simply disconnected and reconnected it, and the problem has not returned.	7
	2000 Saturn LW2 3.0L door locks VIN: 1G8JW82R5Y Thanks to those who responded. What I did was the following, reset procedure, push and hold down the driver door lock switch in the unlock position for about 5 seconds. Thank you Marty	3

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