GM Automotive Technicians Technical Discussion and Fixes for Oct 7, 2008

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	Help Request	Answers
	1994 Buick Skylark Custom 2.3L Stall VIN: 1G4NV5539R Hi everyone thanks in advance.I have a 1994 Buick Skylark that will go into closed loop about 1 minute after a cold start up & the engine will stall or act like it wants to during this period..I check the ground circuit to the PCM & tried 2 O2 sensors (Bosch &...	View
	2003 Buick Regal LS 3.8L Steering VIN: 2G4WB52K13 Customer came for a hard to steer p\s at idling. When engine hot and rpm below 1000 rpm, the steering come hard to steer. If you rev up engine to 1000 rpm or more all is free and you can turn steering wheel with finger... Tried another p\s pump, tried 2 racks,...	View
	1999 Cadillac Catera 3.0L Mechanical VIN: W06VR52R44 I have this vehicle in my shop that someone else took apart. I've checked every source I know to get a vacuum hose Dia,[ie;dealers,on line,ALLdata etc.] Can someone help me with this? Thanks in advance. Larry	View
	2007 Cadillac CTS 3.6L engine VIN: 1G6DP57727 customer has concerns regarding a noise on engine cold start. it sounds like a chain tensioner is a little loose on first cold start. noise lasts maybe 2 seconds. i figure one of the tensioners is bleeding down. caddy dealer told him not to worry about it, it'...	View
	1992 Chevrolet Motorhome 7.4L Mechanical VIN: 1GBKP37N8N When the vehicle came in the release of the drive line parking brake was delayed and the park brake light would not go out. We had some leaks in the parking brake system. We replaced the steering pump, parking brake actuator and pressure switch. All these le...	View
	1993 Chevrolet Camaro 3.4L Cuts out, Misfire VIN: 2G1FP22S7P I am listing this for a friend of mine, he has replaced all the above mentioned parts but still this vehicle is loosing injector pulse on 3 cyls at a time, it will not idle. On 1 ign cycle cyls 1,3,5 have injector pulse 2,4,6 do not. On another cycle 2,4,6 hav...	View
	1998 Chevrolet Malibu 3.1L MIL Lamp on VIN: 1G1ND52M1W hello everybody i hope u can help me i got this malibu it came with check engine light on because it would not pass emission it had code for evap p0440 i check the the vacuum hose for the purge solenoid the hose bas broken replace it ran the evap test with the... Trouble codes: P0440 (purge solenoid weak vaccum)	View
	1998 Chevrolet Cavalier Z24 2.4L Clutch VIN: 1G1JF12T6W This car came in originally for a leaking clutch slave cylinder. We replaced the clutch assembly and slave cylinder with an aftermarket clutch kit. About 2 weeks after that the car came back for a low clutch pedal complaint. I found some air in the system so I...	View
	1999 Chevrolet Venture 3.4L MIL Lamp on VIN: 1GNDX03EXX This Vehicle was sitting next to a tree that was struck by lightning. Towed to shop and was a no start. Unable to communicate with PCM. Checked all circuts from PCM connectors for proper resistence and checked powers and grounds. Replaced PCM and flashed with ... Trouble codes: P0102 (Mass Air Flow Sensor), P0230 (Fuel Pump Relay Feedback), P0403 (EGR Control Circut), P0405, P0605 (Mil Circut Fault), P1554 (Cruise Feedback Circut)	View
	2001 Chevrolet Impala 3.4L Starting VIN: 2G1WF52E21 Thanks in advance for the help. I have an '01 Impala we are replacing the bcm in. For some reason I can't "relearn" it. What am I missing?? I've left the key on for 10 minutes, off for 10 seconds and repeated (many times now). I know I've done this before with...	View
	2003 Chevrolet Astro 4.3L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1GNDM19X03 Normally this Astro runs great but intermitently the low fuel,abs, check guages and security light will flash off and on, check engine light will dimly light up and flicker and vehicle starts to misfire as if ckp sensor is dropping out. At that time I get abou... Trouble codes: P0355, P0341, P0608, P1626, U1064, U1301	View
	2003 Chevrolet Cab & Chassis Silverado 3500 6.6L Excessive Emissions, Black smoke We have 2003 c4500 flatbed tow truck that belongs to our local tow company. It has the 6.6 diesel. There in no active service engine light but it does a p1093 code in memory and a p1643. I cant find a defenition for the p1643, and I am un familiar with the p10... Trouble codes: P1093	View
	2005 Chevrolet Silverado 1500 SS 6.0L MIL Lamp on VIN: 1GBHC24U15 hey guys i am having a bit of trouble on this truck. vehicle came in with a reduced engine power code. checked all data for info and found the was a problem with this vehicle. computer was telling us to replace a couple components which sounded like they would...	View
	2006 Chevrolet Express 2500 4.8L No Start, Stall VIN: 1GCGG29V46 Vehicle in for crank but will not start. Customer commented that security light flashing as symptom is occuring. On going problem for vehicle since new. ***But--- only happens or occurs at this time of year.. The codes found in pcm were not current and initial... Trouble codes: 171 (lean o2), 174 (lean 02), 336 (crank sensor)	View
	1997 Geo Metro LSi 1.3L Air Bag VIN: 2C1MR2298V I have this Metro for air bag light stays on all the time. I cannot access codes with my scanner. Is there a way to manually get codes out of the air bag module? There is not much information in the archives for air bag problems on this model. Any help will be...	View
	1999 GMC Jimmy SL 4.3L speedometer VIN: 1GKDT13W0X after truck is drivin for awhile speedo quits abs light kicks on and trans stops shifting. looking at scanner with truck sitting still all sensors read 4mph can communicate with ebcm so i'm not sure if its a problem anyone out there experience anything similar...	View
	2001 GMC Savana 3500 5.7L Hesitation, Cuts out, Stall VIN: R811900469 as i explaned above this vehicle doesnt have any power. engine never revs up. you can stand on the throttle in park and it will never hit 5,000 rpm. had catalytic converters replaced with no change in performance. vehicle was overheated and blew engine and tra...	View
	2002 GMC Envoy SLE 4.2L Exhaust Noise/Leak VIN: 1GKDT13SX2 Just a quick question for you GM guys, I have a 2002 GMC Envoy with an exhaust noise that sounds like it is coming from the exhaust manifold, it is more noticeable when cold but it is always there, before I start to dig into it, I thought I would ask to see if...	View
	2002 GMC Sierra 1500 5.3L starter VIN: T521364115 we pulled trans. for repairs and reinstalled.when we tried to start the truck,the starter would not engage.starter tested good.all lights,indicaters,switches,etc.are working.security light flashes for approximately 15 secs.no power at starter relay.we put tran...	View
	2005 GMC Sierra 1500 SLE 5.3L volt meter VIN: 2GTEC19T35 hi, custumer came in with a complain that volt meter reader lower than normal,i check the alternator output and it was 12.8 volts, and turned oof the engine and stared again then voltage was 14.8 volts let it idle for about 15 minutes and voltage droped to 12....	View
	2003 Hummer H2 6.0L compressor VIN: 5GRGN23U13 I have this hummer h2 that rattles the a/c compressor belt tensoner at 3000 rpm. a/c blows cold no noise at idle but at high rpm the belt and tensoner chatter violently. compressor not noisey spins freely by hand. Im thinking compressor but has anyone had one ...	View
	1991 Pontiac Grand Prix SE 3.1L Stall VIN: 1G2WJ14T1M Hello. This car intermittently stalls when driving under normal conditions. The previous shop replaced MAP sensor and 2 ignition coils that were cracked. Redbrick OBD1 Snap-On scan tool won't communicate with it. Also, someone installed an aftermarket alarm an...	View
	2001 Saturn L200 2.2L Misfire VIN: 1G8JU52F81 This saturn L 200 has a miss after startup but not right away. It takes a few minutes then #1 starts dropping out. It lasts for about a few minutes then clears out. Checked plug and replaced plug. Also swapped out coil housing and module. Repaced injector and ... Trouble codes: P0301	View
	2005 Saturn L300 3.0L No Start, Hesitation, Surge, Misfire, MIL Lamp on VIN: 1G8JDG4R35 Car came in on the hook. Customer copmlaint: no start. Customer says it sat for 2 weeks than it wouldnt start. Battery looked like it been replace recently (AC DELCO). Tested anyways 12.3v. Next, checked fuel pressure none intially. Added induction cleaner dow... Trouble codes: P0123, P0222, P1779 (p1791-), P1791, U2105, P0700	View

Fixes & Summaries for GM

	Fix/Summary	Answers
	1998 Buick Regal LS 3.8L lifter VIN: 2G4WB52K4W WE RESEIVED A LOT OF GREAT REPLIES RANGING FROM ADDING TRANS FLUID TO HELP PUMP UP LIFTERS, PUSH ROD LENGTHS BEING CROSSED. HOWEVER AFTER ELIMINATING THE LIFTERS AND PUSH RODS BY REPLACING, SWAPPING ROCKERS BACK AND FORTH WE ADVISED CUSTOMER THAT A TEAR DO...	25
	1997 Cadillac Seville STS 4.6L windows, radio VIN: 1G6KY529XV This car is fixed. The problem was the relay box just as several people said. It`s hard to believe that washer solvent could get that far, but it does. I had to replace two relays and clean all of the sockets. Funny, but when we told the customer what we found...	12
	1998 Cadillac Eldorado ESC 4.6L ac compressor VIN: 1G6EL12Y5W i would like to thank everyone that had advice for me. when your stuck on a vehicle, any advice given can be a great help. to dennis and ray, you guys nailed it. there was no metal which tells me the other shop flushed the system well, but the orfice tube was ...	10
	2000 Cadillac Eldorado ESC 4.6L ABS Module VIN: 1G6EL12Y5Y Well this caddy is fixed. Sorry for the delay but our internet has been down for what feels like an eternity. Thanks for the responses. The problem was a simple fix but hard to find. It turns out that the connector on the cruise control is the same as the ...	2
	1970 Chevrolet Corvette 5.7L blower VIN: 194670S406 Removed and disassembled HVAC box. Resealed and all is well. Lot of air blowing where it did not need to be. Thanks for the help.	27
	1988 Chevrolet C2500 Cheyenne 5.7L transmission shifting VIN: 2GCFC29KOJ well we checked everything that we could fine on aldata and from everyone that replied to us and we didn't get it to work. So we took it to tranny shop and the found that the shift selinods have jamed in place and the valve body is badly scored. They are rebui...	19
	1993 Chevrolet C1500 Cheyenne 4.3L Hesitation, Stall, Poor Fuel Economy VIN: 1GCDC14Z5P all you guys are awsome. i am so sick of these crappy vehicles people want you to work miracles on for no money. i have looked at all your email responces. the only thing i didnt do was pull throttle body off. so i did blew all ports out cookied surface and ch...	16
	1994 Chevrolet Astro CL 4.3L power steering VIN: 1GNEL19W6R Well we finally got the vehicle fixed. Steve from New Jersey hit it right on we ended up putting a new gm pump on the van and now everything is working, we ended up replacing the steering box and power steering lines, before we put another pump on due to the f...	6
	1994 Chevrolet S10 4.3L No Start, ecm, no communicatio VIN: 1GCCS14ZXR Found that the wire splices that gm uses are not the best. took engine wire harness apart and fixed 8 splices. now runs good. Thanks to all that helped. Thanks Bob	3
	1996 Chevrolet C1500 Cheyenne 4.3L Misfire, MIL Lamp on VIN: 1GCEC14WXT sorry I took so long to get back. well after modifing distributor so i could advance it, I turned it while running and got a good shock from coil wire. this problem did not show up when i sprayed wires with water.I set timing retard to 0 and put a new set of w... Trouble codes: P0300.	9
	1999 Chevrolet Silverado 1500 4.8L transfer case shifting VIN: 1GCEK14V8X Well this truck is fixed! Thank you all who replied especially James from Wisconsin. Replacing the transfer case shift control module did the trick. I had inherited this one from a transmission shop so I look like a genius thanks to Aitn!	9
	2004 Chevrolet Trailblazer LS 4.2L compression/oil in cylinder VIN: 1GNDS13S64 Appoligies for the long close time... The vehicle ended up going to the dealer for a service contract repair. The customer bought a contract and did not even know it. Sales department at its finest! The dealer removed the valve cover and found that the roc...	13
	1996 GMC C2500 Sierra SL 6.5L Cuts out, Stall VIN: 1GTGC29FOT Thanks for all of the help that I recieved.. I replaced the PMD driver on the injection pump and the oil pressure switch.. i also replaced the lift pump on the rail. Truck left and I have not had any complaints. Thanks for all of the help.	12
	1998 GMC K3500 Sierra SL 7.4L abs brakes VIN: 1GTHK34J6W THANKS FOR ALL THE GREAT TIPS GUYS, UNFORTUNITLY MY CUSTOMER HAS NOT BEEN ABLE TO DROP THE TRUCK OFF SINCE TO CONTINUE MORE WORK ON IT YET. SOON I HOPE, THANKS AGAIN.	23
	1998 GMC K1500 Sierra SL 5.7L Surge, Misfire VIN: 1GTEK19R8W To all; Thanks for the many prompt replies. I checked the cam retard 1st and sure enough -12. I reset that and runs great now. The one thing I noticed when I used my genysis the perform the test, is that the reading is not live, so after moving distributor I ... Trouble codes: P0300 (random misfire).	18
	2000 GMC Yukon Denali 5.7L radio blows fuse VIN: 1GKEK13R5Y Vehicle never returned. Didn't really expect it to. Had some helpful replies stating to unplug radio and drive, check for chaffed wiring behind radio, look for 'custom' wiring and aftermarket parts added to the circuit, and another guy that had an issue with t...	4
	1998 Oldsmobile Intrigue 3.8L Electronic VIN: 1G3W552K9W Hey guys thanks for all your help. Especially Daniel from Cal. and Kerry from Fl. you guys were right on. I had unplugged the actuators. earlier and plugged them back in and heard a groaning noise from the left side actuator but didn't quite know what to do ne...	6
	1992 Pontiac Bonneville SSEi 3.8L digital display VIN: 1G2HY5213N Thank you for the replies, all of which basically said to R&R the cluster and replace it with a rebuilt or remanufactured unit. The customer went to the local dealer and they were able to find one. They first said NLA but then offered a reman unit. The custome...	3
	2002 Saturn Vue 3.0L Mechanical VIN: B32S804897 the problem was a plugged oil passage from the rear main to the upper engine, could not tell what the material was but I have to agree that it looks like melted plastic, the 2 replies I had were correct in pointing me this way Thanks	3

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