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Help Request Answers
1999 Buick LeSabre 3.8L Cuts out
got this buick that cuts out intermittenly the first day i ran it several hours with nothing doing,i then road tested it and it did cut out.it starts right back up with no problems.i let it run again in the shop for almost two hours with the scope hooked on th...		 View
2001 Cadillac DeVille 4.6L No Start
hi guys! I'm working on 01 cadillac deville no crank, also no fuel pressure! when customer brought car, we just replace IAC, and was starting fine. next day when I trying to start there were no crank, and no fuel pump. also it shows low fuel on cluster, so i p... Trouble codes: p1634 (Ignition 1 Switch Circuit).		 View
2007 Cadillac Escalade EXT 6.2L Tire Pressure Monitor
One for you GM dealer tech's.This Escalade had 18 inch tires originally and now has 20 inch tires installed. I was called in to recalibrate the TPM system because I have a Tech II. When I went into the learn mode the scanner said it could not learn LF tire. Th...		 View
1958 Chevrolet IMPALA 283CID 1-2 shift is late
not sure on the tp adjustment on the cast iron powerglide. shift is late unless you lift off of pedal. there is only 1/2" adjustment either direction. maybe the linkage is wrong, been too long to remember for me.		 View
1989 Chevrolet Camaro 5.0L No Start, Poor Idle Quality, Surge
once you get it started and drive it for a block are so it will not restart. It was sarting the next day but now you have to spray starter fluid in the intake. no injector pluse. i have 2.5 volts @ ecm on the ppl wire. All pin checks at the ecm are ok. please ...		 View
1993 Chevrolet Corsica 2.2L Stall
Car was brought to me for stalling, only when wife driving the car, the husband has not had it happen. She says it has been happening for about 6 months. She drives it for about 5 or 6 miles, vehicle stalls but will restart but then dies again when put in gear...		 View
1998 Chevrolet S10 Pickup 2.2L MIL Lamp on
am chasing a p0401 egr flow code, sopposed to have new head, have checked egr with scanner, commanding 100% egr will make engine stumble but not die, ports look clean but it has that plate that bolts to back of head and can't get to it to check ports, pull egr... Trouble codes: p0401 (insuff egr flow).		 View
1999 Chevrolet Pickup 5.7L No Start, MIL Lamp on
Hi Everyone. I have this truck is in the shop for a no start. It started out not having spark. I fixed that problem. First i put a crank sensor in for code P0338. This took care of the code. There is also a tsb for that code. I also had to put an ignition cont... Trouble codes: P0338 (ckp Sensor Circuit High Duty Cycle), P1361 (Ignition coil control circuit low Voltage).		 View
2000 Chevrolet Impala 3.8L air bag light on
Air bag light flashes and stays on. Code b41 found with statement see service manual. Mitchell shows no listing for this code. Checking data shows driver and passenger airbag loops enabled. Using scanner to erase code give message code erased however code is s...		 View
2001 Chevrolet Cavalier 2.2L Poor Idle Quality, Hesitation, Misfire
Vehicle has severe intermittent random misfire, Tech2 will indicate all cylinders misfiring or just 1 and 3 or 2 and 4, when problem occurs you can hold the throttle so misfire will continue for minutes. all scan tool parameters appear normal on freeze frame d... Trouble codes: P301 (Random Misfire).		 View
2001 Chevrolet Monte Carlo 3.8L locks and starting
I have a question about the BCM on this vehicle and some direction on where to concentrate my test. The vehicle will not start after sitting for about 10 minutes with the key. The power locks also do not work. There is just nothing happening at all. After the ...		 View
2001 Chevrolet Express 5.7L serpentine belt
This Van has been throwing the serpentine belt off every 3 weeks or so. I have used the original belt, tensioner, & idler the last time and it lasted 3 weeks again. I don't see any problems with alignment, or any pulley problems. Ihave even turned the steering...		 View
2002 Chevrolet Corvette 5.7L MIL Lamp on
this vette came in with an intermittent SES light, ABS light, traction control light, fuel gauge inop. also lost all driver door controls(windows, locks etc.) customer said he turns the car off and then everything is fine. it has done it twice this year for hi... Trouble codes: u1301 (class 2 serial data link high), p1626 (anti-theft system fuel enable circuit), u1096 (lost comm with IPCDIC or class 2 TXD), u1016 (lost comm with ECMPCMVCM), u1064 (loss of BCMDIMSBM comm), u1176 (loss of RFA comm).		 View
2003 Chevrolet Avalanche 5.3L engine
customer brought this one in with a noise that sounds like a belt chirp. after looking at it we found that the noise is coming from the left valve cover area. we removed the valve cover to find that the rocker arms seemed dry. we started the engine with the va...		 View
2005 Chevrolet Silverado 5.3L A/C control head
I have one of the strangest a/c problems I have ever seen and really need some help. This vehicle has dual zone automatic climate control. You can do anything you want with the hvac and it perform wonderfully. Blows hot, cold, in all modes and zones. When you ...		 View
1993 Geo Tracker 1.6L No Start
I have a 93 geo tracker in the shop, The owner of the vehicle has attempted fixing it for the last few months and god only knows what he has messed up. I have checked mechanical timing, it is good. I checked to make sure the ingnition system was firing at the ...		 View
2000 GMC Savana 5.7L engine races
hello fellow techs , hope you can help with this one . i have this gmc savana van that came in for a stalling condition and tps voltage jumping around . i found the tps connector ground wire broken in the insulation at the tps sensor . replaced tps sensor and ...		 View
2001 GMC Savana 5.7L Poor Idle Quality, Misfire
Vehicle came in with the complaint that runs bad cold and when warmed up it seems to run fine. Number 1,2 4,6 cylinders are misfiring, do not change with shorting them. Checked fuel pressure, codes none found, check misfire counters and there were none, moved ...		 View
1999 Oldsmobile Intrigue 3.8L headlights
high and low beams inop after car is warmed up.flash to pass light on dash also stops working but outside lights still work.lights work when car is cold.		 View

Fixes & Summaries for GM
Fix/Summary Answers
2001 Cadillac Catera 3.0L Misfire, MIL Lamp on
First of all, thank you very much to all the fellow technicians who took the time to share their knowledge and experience with me. Almost all responses pointed out to a faulty maf or out of calibration. They all were right. And also this guy who took the tim... Trouble codes: p0171 (system too lean b1), p0174 (system too lean b2).		 11
1988 Chevrolet Pickup 4.3L Poor Idle Quality, Hesitation, Cuts out
I want to thank everyone for there help.Yes I have fixed this one As a last resort I put a distributor in the vehicle and it runs like a top.I hessitated doing this because the customer said he had already replaced the distributor when the engine was re...		 16
1995 Chevrolet Caprice 5.7L poping sound
Hi Guys.I check the and see if the valves moved properly and it looked good. I put the vacumn guage on it and it looked good with a slight movement.Pulled the pcv to see it the intake was sucking vacumn.Put in a new iac and that didn't do anything either.Left ...		 52
2000 Chevrolet Blazer 4.3L immobilizer
We have run through all of the suggestions from all of the replies - thanks to all who replied - but the fault still remains. The vehicle previously (when the key fobs worked) would start and then cut out 2 seconds later. Once the unlock was pressed on the rem...		 6
2001 Chevrolet Impala 3.4L MIL Lamp on
Thanks for all your help guy's. It was the BCM put a new one in and programmed it and that took care it.I tested continuity and voltage's in all wire's and did the terminal drag test before replacing Thanks again Mark Trouble codes: B2960 (Ignition passlock module).		 17
2002 Chevrolet Avalanche 5.3L Poor Idle Quality, Hesitation, Misfire, MIL Lamp on
THIS MORNING I TESTED BACKPRESSURE BEFORE THE CAT (B1). I FOUND 10PSI. THEREFORE, THE CAT WILL HAVE TO BE REPLACED BEFORE GOING ANY FURTHER. THANKS FOR ALL OF THE GREAT REPLIES AND IDEAS. ERIC Trouble codes: P0300 (multiple cylinder misfire detected).		 7
2003 Chevrolet TrailBlazer 4.2L Hesitation
Well this one is going to the Dealer. I completely forgot about the 8/80,000 warranty on the pcm(thank you guys for reminding me) This is what we are leaning towards as being bad. Customer of course says it hasn't acted up in the last 2 days. Trouble codes: p1280 (Accelerator pedal position sensor 2 error), p1271 (Correlation code between 2 pedal pos. sensors).		 6
1990 GMC Suburban 5.7L Excessive Emissions
We found that a pos. backpressure egr valve cured the high NOX. We tried useing OE tire size to no help. In checking the back pressure at the egr port found high back pressure under load, this was turning off the neg pressure valve. Cause is probably the heade...		 10
2003 GMC Sierra 4.8L Poor Idle Quality, Hesitation, Misfire, MIL Lamp on
We finally sent it to a GM Dealership where there diagnosis was the thrust was out causing too much end play not alowing the crank sensor to pick up a good signal. Will need crank replaced or used engine installed. Thanks for everyone who tried to help me out ... Trouble codes: p0336 (Crankshaft position sensor).		 7
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