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International Automotive Technicians Network
Prev Professional Automotive Repair Technical Discussions for January 30, 2008
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Open Help Requests for GM
Help Request Answers
2000 Buick LeSabre Custom 3.8L p0420 VIN: 1G4HR54KIY
vehicle originally came with no power and check engine light on. replaced catalytic converter because it was plugged. replaced o2 sensors because slow reaction, ran on the rich side. returned a couple times for dieing problem replaced crank sensor. came back a... Trouble codes: P0420 (catalyst inefficiency)
1997 Cadillac DeVille 4.6L Hard start when cold VIN: 1G6KD54Y5V
I first checked the fuel pressure it was low 42psi koeo, so replaced pressure regulator now it has 52psi koeo as soon as turn key to run and holds, still very hard cold start. Pulled plugs they looked slightly fuel fouled. so replaced with AC plugs still same ...
1993 Chevrolet Lumina Z34 3.4L Excessive Emissions VIN: 2G1WP14X4P
This Lumina is failing the Nox portion of the ASM 50/15 State emission test. In addition it would idle at over 2,000 rpm when cold started. Smoke testing revealed a very large vacuum leak at the lower intake manifold gaskets. Further testing revealed an O2 sen...
1996 Chevrolet K1500 Cheyenne 5.7L Poor Idle Quality VIN: 2GCEK19R7T
customer came in with the truck idling about 2500 rpm,checked for external vacume leaks with propane along withe a smoke machine to try to find a vacume leak.ohmed wires from vcm to iac all ok. iac counts are 0 the maf is 20.3gm/sec map is 8.6hg and .96volts.t...
1999 Chevrolet Express 3500 6.5L No Start VIN: 1GDJG31F2X
The owner came to me a couple of weeks ago with a no start condition. we towed the van in and found that the lift pump was allowing fuel to drain back to the tank over-night,so we replaced it. The van started good for about a week, and then, no start. I tried ...
1999 GMC K2500 Sierra SLE 7.4L No Start, Cuts out, Stall VIN: 1GTGK29J8X
Intermittent stall when driving or no start when cranking. Unable to duplicate condition in shop (of course!!!). Fuel pump is drawing 10 amps. 6 ohms resistance on ground side of pump. Cleaned all grounds, no change. Ran jumper wire ground direct to battery, n...
2003 Hummer H2 6.0L RF Dash VIN: 5GRGN23U53
This Hummer is making a rattling noise in the RF upper dash area. I am unable to locate it and thought I might ask for help before I start tearing it apart. Any insight would be appreciated. Thanks
2006 Hummer H2 6.0L Hesitation, Surge, Poor Fuel Economy VIN: 5GRGN23466
H2 coming in tomorrow, did field test and got these codes. If anyone has had the same problem would be great for an advantage on this repair, as i'm not a G M tech when driving the car would all of a sudden drop 4 cylinders, well that what it feels and sounds ... Trouble codes: U0107 (lost comm with throttle actuator), P0200 (injector control circuit), P0300 (engine misfire drtected), P1626 (theft deterrent enable signal not received)
1993 Oldsmobile Cutlass Supreme S 3.1L Hesitation VIN: 1G3WH54T0P
Hello all, hope someone can help us. We have a 1993 cutlass supreme not playing nicely. It has a "tip in" hesitation from a stop when engine cold and code 35 idle speed error. It goes away as soon as engine temp reaches 150-170 degrees. If you accelerate hard ... Trouble codes: 35 (idle speed error)
1999 Oldsmobile Silhouette Premiere 3.4L fans VIN: 1GHDX.3EXX
Hello felllow techs,The customer complaint is that this vans temp guage goes to or just above the halfway mark when it idles for extended periods, she also seems to feel that it runs rough when this happens(I never experienced this),she also added about a pint...
2003 Saturn Vue 3.0L Hesitation, MIL Lamp on, Power loss VIN: 5GZCZ63B83
Vehicle came in for wheel bearing work, brakes and power loss with MIL on. Checked for codes and found the three listed, did some preliminary research with minimal results. Cleaned the throttle bore, checked the spring tension on the drive-by-wire throttle pos... Trouble codes: P0638 (Throttle command performance), P0700 (Mil request by TCM), P1780 (Transmission PNP switch/Mil request by TCM)

Fixes & Summaries for GM
Fix/Summary Answers
2003 Cadillac DeVille 4.6L abs VIN: IG6KD54Y63
1992 Chevrolet S10 Blazer Sport 4.3L Hesitation, Cuts out, Stall VIN: 1GNCT18W1N
I have determined the next step is to open the upper intake to inspect CPU tubes & assembly. Customer is not able to spend $ on diagnosis at this time.
1997 Chevrolet Cavalier 2.2L wipers VIN: 4J23HJ341H
thanks to all of you who responded,most of you guys were dead on.it was indeed the parking pawl spring that was broken,its repaired now ...Iatn still rocks..thanks again doug.
1999 Chevrolet Silverado 1500 5.3L Engine VIN: 2GCEK19TXX
As many replies suggested, found fuel pressure regulator seeping fuel into intake vaccuum port, causing cylinder # 4 and 6 plugs to be dark, and setting the Po304 code. Replaced regulator / cleared code & retested, ok. Thanks to all who took the time to ...
2001 Chevrolet Astro 4.3L bind up slight turn VIN: LGBEL19W81
Hello, I can not say if this one is fixed I haven't heard back from customer. We did find the idler arms right very loose left a little loose and left axel sleeve was not locked in frt diff. the tires was worn pretty bad. Customer took the vehicle and got thos...
2002 Chevrolet Tahoe LS 5.3L interior lights VIN: 1GNEK13Z82
We found out later that the vehicle had been to both GM dealers in our town. No mater what we checked we could not get rid of code 2618 which kept the courtsey light relay from grounding the circut at BCM. We tried to find out if the calibration for the interi...
2003 Chevrolet Silverado 1500 4.3L Starting VIN: 1GCEC14X53
Great News! This truck is fixed and running strong with a new cap and rotor. Thanks for the heads up on a closer inspection of the ignition system. We had changed all the secondary igntion parts 15000 miles ago but for some reason the cap failed. The truck sti...
2005 Chevrolet Suburban 1500 LS 5.3L belt squeek VIN: 1G2HUI4569
thanks to everyone got the vehicle back in the shop and most everyone said check the ps pump pulley and sure enough it was not pressed on all the way pressed pulley on and squeek is gone now thanks again everyone for the help
2001 GMC Sierra 1500 SL 5.3L MIL Lamp on VIN: 2GTEC19T91
I believe this one is fixed, so far it has not reset the codes. Thank you very much Alex for the information about the Calibration update. It would have been nice if my Alldata system would have listed a service bulletin for this fault, but it didn't. Once ag... Trouble codes: P1133 (b1s1 insufficient switching), P1153 (b2s1 insufficient swiching), U1041 (loss of ebcm/ebtcm communications).
1996 Hummer H1 6.5L vss VIN: 137ZA8435T
contacted auto meter was told to catch the signal before the pcm this was un sucessful i got looking at the diagram found it went into tcm first so we tapped into the wire before the tcm all is ok the tcm buffers the signal for the pcm spedo works...
1995 Oldsmobile Aurora 4.0L No Start, Hesitation, Stall VIN: 1G3GR62C6S
thanks to everyone that replied. the mistake that was made was the owner told me along with all the other repairs he made himself he replaced the fuel pump. when i quized him further he was mistaken. new fuel pump did the trick. last time i take in something t...
1995 Oldsmobile Aurora 4.0L Hesitation, Stall, Misfire VIN: 1G3GR62C2S
Thanks for the help fellow tech's, our problem was a defective injector, it was partially restricted?? Ck'd fuel filter was not clogged but was loaded w/sediment.
1998 Pontiac Grand Am SE 3.1L windows VIN: IG2NW12M6W
the carpets are a little wet but not anymore than the other vehicles coming in.never found anysigns of water intrusion.over the weekend were going to let the care sit in the shop with afan on it and try to dry it a little for them.thank you for your comments
2002 Pontiac Aztek 3.4L odometer light VIN: 367DA03E62
I asked the owner if I can open the cluster and try to FIX it...the answer was: Just get the rebuild one...Rebuild cluster FIXED the problem...thanks...PRO's...
2003 Saturn Vue 2.2L Elec power assist VIN: 5GZCZ23D93
Had a freind of mine that has a tech 2 and reprogamming ability and we atempted to program the column module and had no luck his software had no saturn info at all. So Took to saturn dealer and they reprogrammed the Column module and the BCM, seems to work fin...
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