GM Automotive Technicians Technical Discussion and Fixes for Aug 1, 2005

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	Help Request	Answers
	1986 Buick Riviera Luxury 3.8L Poor Idle Quality, Cuts out, Stall, Misfire VIN: 1G4EZ57B1G Hello all and thanks for your help, I've been working on this car for several months. (He brings in money and then I work on it again) It has a very rough idle in gear and will stall at lights both on accel and decel. The engine will idle in park for extended...	View
	1992 Buick LeSabre Custom 3.8L No Start, Cuts out, Stall VIN: 1G4HP53LON Problem is very intermittent. Customer says the vehicle stalls as if you shut the key off. I'm thinking ignition module, crank sensor, or ECM fault. I tried tapping and wiggling wiring to all of these, but nothing conclusive. The customer said the last time it... Trouble codes: 17 (RPM Signal Problem)	View
	1999 Buick Park Avenue Ultra 3.8L power door lock VIN: 1G4CU5218X Greetings, Have a strange intermitent problem.Customer claims vehicle unattended with doors unlocked,will lock drivers door only.When returning it takes repeated attempts of hitting remote to get drivers door to unlock. At other times all 4 doors are locked,a...	View
	2000 Buick Park Avenue Ultra 3.8L No Start VIN: 1G4CU5413Y Car came in with security light flashes & no start , code B2069 in the pcm, replace &reflash pcm ,car start, but the security light stays on & code B3031 in the memory. any help...thanks Trouble codes: 3031 (key decoder device in assembly learn mode)	View
	2002 Buick Rendezvous CX 3.4L abs system VIN: 3G5DB003E2 vehicle's abs system will activate when brakING at very low speeds of 15 mph no code in system all sensor are reading correctly problem is intermittent.	View
	1990 Chevrolet Corvette 5.7L air bag VIN: 1G1YY2381L we had to send the cluster instrument for repair, and at the same time we decided to replace the ignition switch that was hard to turn at times. After putting everything back together we found out that the seat belt and the air bag light were on. We tried to g...	View
	1991 Chevrolet Lumina Euro 3.1L Noise VIN: 2G1WN54T2M This car came into our shop with a very noisy fuel pump, buzzing it's little brains out. You could hear the car coming up the street. Pressure, volume and supply voltage were, surprisingly, OK. I did not check voltage drop across the pump, amps draw or scope p...	View
	1992 Chevrolet Lumina Euro 3.1L No Start, Stall VIN: 2G1WN54T3N This car came in with an intermitant stall and not start. Let it set for an hour and it would start and run. I found when it wouldn't start it had good spark but no fuel pressure. A check of the wiring proved power was getting to the fuel pump but it wasn't ru...	View
	1995 Chevrolet Blazer 4.3L Cuts out VIN: 1GNDT13W4S Hi guys, This Blazer has a severe bucking/cutting out only when under load. No problem cold and idles just fine hot. EGR desired and actual 0% at idle and up to 70% under load hot. It came in with no code but was able to set 32 after much testing while power b...	View
	1997 Chevrolet p30 chassis 454CID Surge, Stall, engine dies in gear VIN: 1GBLP37J9V Engine siezed up replaced with a gm new 454 After install start engine set cam timing 0 Put into gear reverse or drive engine dies trys to run surges then dies. Neutral runs up fine no hesitation no stall no die snap on scanner says iac motor is at 215 to 105 ...	View
	1998 Chevrolet Express 1500 4.3L No Start, Poor Idle Quality VIN: 1GCEG15W3W This van will not start at first attempt. Has spark and fuel. If you keep trying it will eventually start, but as you try to apply throttle it will die. Eventually it will get going if you feather it. Scantest found no codes. What I found was the coolant temp ...	View
	1998 Chevrolet K2500 Cheyenne 7.4L long crank time VIN: 1GC0K00JOW Last year i installed a new carter fuel pump due to dead pump, customer complained of hard start i checked and replaced regulator (GM),it was leaking also, still has a long crank, the fuel pressure will hit 58-60 psi and bleed down within 5 sec. So i pulled pl...	View
	1998 Chevrolet Express 2500 5.0L No Start, Cuts out VIN: 1GCFG25MXW The engine turns over AND STARTS, BUT CUT RIGHT OUT. The only way it starts if I spray fuel injector cleaner into the intake but once I stop spraying it shuts off. It will start if I jump the ECT wire and disconnect the TPS. Once it runs I am able to accelera...	View
	2001 Chevrolet Blazer LS 4.3L Poor Fuel Economy, MIL Lamp on VIN: 1GNCS13W51 This thing came in with a complaint of MIL on and poor fuel economy...Scanner revealed bank 1 and bank 2 rich codes. Long term fuel trim was at -12 to -14. Tested fuel pressure, was @62 psi but did not hold...would drop down to 25psi within a matter of one m...	View
	2002 Chevrolet Trailblazer LS 4.2L MIL Lamp on, low power VIN: 1GNDT13S22 Appears to occur at cold start, freeze frame data 0RPM, ECT 66F, Engine load 100%. Alldata and Mitchell don't appear to address this issue or I missed it. Thanks for any help. Trouble codes: P0606 (ECP/PCM Processor fault)	View
	2002 Chevrolet Tahoe LS 5.3L No Start, Cuts out VIN: 1GNEK13Z92 Vehicle was towed in. Failure occured at 70MPH after 45 minutes of driving. Vehicle shut off clean and would not restart. Fuel gauge indicated empty, added several gallons, no change in gauge, checked for codes, none found, found no fuel pump operation. Perfor...	View
	2002 Chevrolet S10 2.2L running rough VIN: 1GCCS19581 car came back - customer claiming the car is doing the same thing - runs o.k. but somtimes sound like missing or want to go off- check for code - there is no code - positive battery terminal shows some battery dis-charge.	View
	2003 Chevrolet Silverado 1500 4.3L No Start, MIL Lamp on VIN: 2GCEC19X63 this truck will not start and has codes p1626 and u1300 i have very little info on this i called mod and they said they would fax me info that was 8 hours ago the theft light dose not flash but dose come on i got differnt key and i tried to rest the theft syst... Trouble codes: U1300, P1626	View
	1996 GMC K1500 Suburban 5.7L Heater control VIN: 1GKFK16RXT Hi! Bottom line here is poor AC from front unit. Cannot find test for heater control "switch" on fire wall. Has vacuum to it, Wiring has a two lead connector - one side has good ground other is "dead" at any AC/Heat setting. Hoses stay hot. All other controls ...	View
	1992 Oldsmobile Cutlass Ciera 3.3L Excessive Emissions VIN: 1G3AL51N5N car came in for an emmision fail. nox being the failure with 1001 ppm with cut point at 450. replaced 02 sensor, cleaned maf sensor replace cat with aftermarket,decarboned upper intake and run a motovac as well with no improvement. maf readings are 5 to 6 gram...	View
	1997 Oldsmobile LSS 3.8L Hesitation, Surge, Cuts out, Misfire VIN: 1G3HY52K6V After the vehicle runs for 45 minutes to an hour,there is a severe bucking and surging between 30 to 40 m.p.h. While watching scan data, there are low misfire counts on cylinders 1,3,5,and 6. Number one is the most common usually showing one to six misfire cou...	View
	1998 Oldsmobile Intrigue 3.8L a/c switch VIN: 1GCEG25H4S start car, a/c works fine.. after a short drive, the a/c light goes off and quits cooling. will come back on after cools off. customer replaced a/c control head with factory part. is it possible the pressure switch on drier could be problem? i'm a foreign car ...	View
	1946 Pontiac N/A CID Coil Wiring Hi all, I am in the process of re-wiring this old Pontiac; nothing fancy, just make it run and safe; don't worry about keeping it original. The problem that I've run into involves the coil wiring. I can't find a decent diagram and I can't figure out if this o...	View
	1999 Pontiac Grand Am SE 2.4L No Start, Stall VIN: 1G2NE52TXX Here we go...this is a wild one. The Grand Am while driving down the road the ABS, security, MIL, Traction off lights all come on. Upon inspection I found U codes in all modules that say loss of comminucations basically. This thing does not do it all the time ... Trouble codes: U1000	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	1995 Buick Riviera 3.8L Cuts out, Stall, MIL Lamp on VIN: 1G4GD22K35 thanks again too all that replied, come to find out customers child has admitted this stall in reverse problem has been going on for about a year. and they chose to take vehicle as is, I did proir to posting replace t.p.s, and tried a known good pcm, also ran ... Trouble codes: P0123.	6
	1990 Cadillac Allante 4.5L ABS module VIN: 1G6VS3382L The fix was to replace the ABS pump motor. It was getting power, but not pumping to correct pressure. It was an easy repair, but cost the customer $2200.	2
	2005 Cadillac CTS V 5.7L tire pressur VIN: 1G6DN56S05 thank you all for your help I had to take it to the dealer to reset the tire pressure sensor. We made the mistake of moving the right front tire to left front and vice vera. The local dealer scanned in the reset the sensor now we are happy campers.	12
	1993 Chevrolet Lumina 3.1L Excessive Emissions, Poor Idle Quality, Hesitation, Stall VIN: 2G1WL54TXP After checking resistance of the injectors and finding everything within spec, removed the alternator and checked the output and find that it's a bit under spec, so that couldn't be frying the PCM. When vehicle was in previously, there was a misfire that hadn'...	8
	1995 Chevrolet Tahoe LS 5.7L abs VIN: 1GNEK13K9S Well I had some replies(3) suggesting to address the front wheel speed sensors,and one to address the abs controller.The fix turned out one of the valves inside the controller was sticking when the abs would come on.The reason the abs was coming on ,rust build...	6
	1996 Chevrolet Blazer 4.3L brake pedal feel VIN: 1GNDT13W2T What a difference a weekend makes. When I had a chance to work on the car Monday it was much quieter in the area around my shop and I could plainly hear a vacuum leak if I really pressed hard on the brake pedal. Obviously there was a vacuum leak in the brake b...	17
	2001 Chevrolet Blazer LS 4.3L electric window VIN: 1GNCS13W51 As most suggested the switch was the culprit. When the window hits the bottom of it's travel the extra current trips the switch. Thanks again to all who offered their time on this one.	9
	2001 Oldsmobile Aurora 3.5L ebtcm VIN: 1G3GR64H61 Thanks to all who responded. Unfortunately, I had to wash my hands of this vehicle. I attempted everything in my power to reconfigure the module, including trying each calibration program available through SPS. I advised the customer (used car lot) to bring th...	4
	2001 Pontiac Grand Am SE 3.4L No Start, MIL Lamp on VIN: 1G2NF52E41 Thanks to Timothy ,Kyle, Jeff, Robert, Ronald , Jim , Ron and Matt on ideas and possable solutions -- Of course after the above occured there has been no reoccurrance of problems BUT I am going to attack each of the ideas you have given me and try to make this...	8
	2000 Saturn SL2 1.9L MIL Lamp on VIN: 1G8ZK5279Y Hello Techs, I received some good information on this problem. Thank you to the techs that responded. Ross [...] suggested a possible loose connection at PCM terminal J2-14. I removed that terminal from the connector & checked the fit on the PCM pin. It w... Trouble codes: P0442 (EVAP small leak detected).	8

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