iATN Member GM Auto Repair Tech Exchange for July 21, 2008

Prev	iATN Members TechHelp for July 21, 2008 Automotive Technical Exchange for the Automotive Repair Professional	Next
(Also Available: All, Asian, Chrysler, European, Ford, GM.)
Vehicle Owners: If you are seeking an automotive repair professional to service your vehicle, visit the iATN Repair Shop Finder.

Open Help Requests for GM

	Help Request	Answers
	1987 Buick Electra 3.8L No Start This car was towed in from another shop with a no start condition. The previous shop changed the timing chain, cam interruptor magnet, cam sensor, crank sensor, crank sensor pigtail, ignition module, coil pack assembly, and the Ecm. I've gone over the alldat...	View
	1991 Buick Century 3.3L No Start Family problem: Car is out of town, belongs to son's girl friend. Car stalled while driving, has good spark from all three coils. No injector pulse. Has 45 lbs of fuel pressure. Has 12 volts to injectors. Had coil paks replaced a month ago. Car ran fine untill...	View
	1995 Buick LeSabre 3.8L volt lite on checked electrical system. no battery voltage on "l" terminal when running. according to schematic comes from volt lite thru pcm to alternator. ready to replace pcm but never encountered this problem before. is there something i missing in my diagram ? thanks ...	View
	2002 Buick Rendezvous 3.4L Radio I have this 2002 Buick here that everyonce in a while it will leave the radio on when you turn the key off. It will stay on but you can't control it at all. It will not go off unless you pull the 60 amp fuse under the hood. Anyone seen this before??	View
	1974 Chevrolet Corvette 5.7L brake This came in to the shop with a brake pull to right. Owner has only owned it for 8 mos. and only has driven it 3 times. It pulls to right. We inspected the brake system and found the left caliper replaced, all new pads, new master cylinder and front brake hose...	View
	1991 Chevrolet Corvette 5.7L Poor Fuel Economy Thanks in advance for help, car came in complaint of running too rich, scoped o-2 and found it was slow so I replaced it, map sensor showed just out of range so replaced it too,nothing has changed the co readings. scoped inj. pw, iat,cts, tps, all normal. inte...	View
	1997 Chevrolet Tahoe 5.7L Misfire Vehicle came in for running bad and misfire. Found pressure regulator leaking (of course) so we replaced injector and we found #4 spark plug fouled with oil to the point that you couldn't see the electrode. We replaced plugs, cap and rotor and now instead of h... Trouble codes: P300 (Random misfire), P304 (4 misfire).	View
	1997 Chevrolet Astro 4.3L Excessive Emissions, Poor Idle Quality, Surge, Cuts out, Stall, MIL Lamp on i have posted this car before i still havent repaired it. the engine runs bad loads up stalls. all the pid data fluctuates with the bad running engine. tps map cts ait egr aly the pid changes even when the engine is just trying to iidle or if i accelerate. i ...	View
	2000 Chevrolet Astro 4.3L No Start hi ihave this astro with no fuel to the cylinders it has 65p.s.i. pressure. the van came in w/no start condition, found no spark replaced cap&rotor got spark,still no start,replaced plugs,distributer,crank sensor. the strange part is it won't start even if i f...	View
	2000 Chevrolet Cavalier 2.2L MIL Lamp on, runs fine hello everyone i have a mill lamp on , no codes no com, runs fine ,tugged on wire harnness to ecm that runs across below radiator,at this point i scanned for codes and none were found and light went out for three weeks ago and just came back on , what i suspec...	View
	2000 Chevrolet Cavalier 2.2L No Start I am not a Chevy guy so I thought I would try you guys. I am a tech with extensive years on Fords. We have a 2000 Caviler in our shop (towed in) and it will not start. Cranks great, fuel pump is cycling and works fine, filter is new, I have spark at the plugs....	View
	2000 Chevrolet S10 Pickup 4.3L Cuts out when you drive this truck cold it runs normal..when it comes up to temp truck it idle great, but when u accelerate it bogs down.like the fuel turns off..but fuel pressure is normal..the only thing i havent done is cut the front of the convertor lose and look i...	View
	2003 Chevrolet Express 6.0L power steering pump It appears to me that I am having a pump problem. I don,t have a pressure tester but I can clamp off the pressure hose and get very little to no response from the change in the pump soound.	View
	2004 Chevrolet ROLL BACK 6.0L Hesitation, Surge, Cuts out, Stall, MIL Lamp on I NEED HELP FROM ANY CATERPILLAR TECH,OR GM TECH.This is what I have,I bought a 04 chevy rollback with a cat engine in it.I have had this truck for almost a year now and have had this problem to come and go several times.Well it started out that the yellow lik...	View
	2004 Chevrolet Astro 4.3L serpentine belt hi and thanks ahead for any help this has me stump ; customer bought van used about month ago it came in day after he bought it with a belt noise we check and found serpentine belt cracked, tensioner and idler noisey, up and down bearing play in alternator so ...	View
	1994 GMC Suburban 5.7L Hesitation, rich on start up Hello to all once again. We have this GMC Suburban in the shop that is driving us nuts. On cold or cool starts it runs real rich if you tips into the gas. Black smoke coming out of exaust. We have checked and swaped (at customers request he has two of them) ma...	View
	2003 Oldsmobile Alero 2.2L Poor Idle Quality, Stall Car came in with a rough idle and a stumble when the a/c compressor kicks in causing the engine to stall at times. Also had a rich exhaust code set. Customer purchased this used car about 6 months ago and it ran great. She is a visiting nurse so she runs on ba...	View
	1998 Pontiac Bonneville 3.8L Stall This pontiac has a very intermittent stall problem which generally occurs on deceleration. Each time it occurs it sets a po102 code. Power and ground to the sensor and the 5 volt square wave were monitored in the shop on a lab scope with the engine running. Du... Trouble codes: po102 (low input - maf sensor).	View
	1997 Saturn SC1 1.9L Shift this car has blown off 2 carquest filter and one saturn filter. The first one was put on after a flush. the car came back complaining of hard shifting then blow off filter gasket. I got it in replaced filter and replace the valve body with new solenoids. reset...	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	1999 Buick Regal 3.8L MIL Lamp on After doing some driving with this vehicle I removed some catalyst from the convertor and the problem went away. So what we had was a partialy plugged convertor backing up the exhaust but not causing any other drivability problems.Weird. Put a new convertor on... Trouble codes: p1133 (h0s insufficient switching sensor 1).	9
	1969 Chevrolet nova 305CID 202 camel back heads thanx for the help very, appreciated.everybody had good info.i dont know why i was thinking it would be different. iknow it would be different for aluminum.this is my moms car.thanks again	21
	1992 Chevrolet Pickup 4.3L fuel guage THERE IS A PART CALLED A DAMPER MODULE AVAILABLE FROM GM THAT ADRESSES THIS CONCERN A FELLOW IATN MEMBER GAVE ME THE #. THERE IS A ALSO A THECH BULLETIN I TRACED DOWN THAT RECOMMENDS THIS PART #. THE TSB # IS 76-83-05. THE PART NUMBER FOR DAMPNER IS [...].T...	5
	1994 Chevrolet Astro 4.3L Electronic Thanks for your help. It is fixxed. First I'll explain that the drac stands for:Digital Ratio Adapter Controller. Another name for it is Vehicle Speed Buffer. First, I checked the fuses. They were good. Next, we raised the drive wheels off the groun...	11
	1995 Chevrolet Astro 4.3L Poor Idle Quality, Surge, Cuts out, Stall hi there thanks to iatn and all its members for ther support it turned out that the distributor gear was warn causing eratic idling replaced the distributor its a fix	12
	1999 Chevrolet Express 5.7L Cuts out Thanks for all the info have replaced the coil like so many said and fix this vehicle	3
	2001 Chevrolet Prizm 1.8L detonation This car still pings too much.checked valve timing again,and advance solenoid. no problem found. chevrolet has been no help. the toyota dealer reflashed the ecm it may have helped a little.there is no egr system.the engine temps are ok and intake air temp sens...	19
	2001 Chevrolet Venture 3.4L No Start most of replies were right on. it was a bad connection at the fuel pump connector at the body	12
	2003 Chevrolet Cavalier 2.2L Unknown Well we have not fixed this one yet, but after getting customer to return for further inspection we received a post and a phone call informing us of the block having an actual casting problem and will seep oil. This appears to be the case here because there i...	10
	2004 Chevrolet Impala 3.8L MIL Lamp on This problem was intermittent so I waited until code came back before i brought back in. I took Daniel's advice first and isolated the vent valve and pulled a vacuum with a mity vac, found no problem. Then I took Richard's advice and energized the vent soleno... Trouble codes: P0455 (Large Evap leak).	6
	2006 Chevrolet HHR 2.4L MIL Lamp on Vehicle has not been back. I still have no idea what might becausing this one Trouble codes: P2135 (TP Sensor 1-2 Correlation).	5
	2002 Oldsmobile Bravada 4.2L rear air ride I found small air leak on top of one of the air bags. thanks to all who helped!!	4

(Also Available: All, Asian, Chrysler, European, Ford, GM.)

International Automotive Technicians' Network