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Prev Professional Automotive Repair Technical Discussions for February 3, 2010
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Help Request Answers
2003 Buick LeSabre Limited 3.8L Surge, Stall VIN: 1G4HR54K23
Car came in with an intermittent surge and stalling. most likley to happen after 1 to 2 miles of driving. was able to duplicate the first time in pulling up to a stop light and it would surge up to about 1100 rpm but never did stall. tuned up plugs, wires, thr...
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2003 Cadillac CTS 3.2L pcv VIN: 1G6DM57N83
Now about a year later it is doing the same thing.I contacted the local Cadillac dealer and they said to blow out pcv system and let it dry over night and put back together and drive it.If any one has any other ideas with this problem or advise would be helpfu...
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1962 Chevrolet C10 Pickup 5.4L low geared VIN: 2C154L1235
the truck i have is not geared to to drive on the freeway, it puts to much on the motor. I believe that that if I change the gear ratio or the rear end that and i can inprove my fuel consumption and reduce engine load
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1986 Chevrolet K20 Suburban Silverado 5.7L Excessive Emissions VIN: 1G8GK26M1G
hi guys,this truck is failing for nox at 15 and 25,port in manifold is plugged,customer does not have the money for manifold removal and i don't work on this old of a vehicle very often-which way does the port go into the manifold so i can try to poke it clear...
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1992 Chevrolet Lumina 3.1L No Start VIN: 2G1WL54T4N
we troubleshot this to the injectors. would not light the noid lite. initially had bad voltage drop on ground side. i had the ecm out and laying on the fender and finally whacked the computer with a dead blow and the noid lit up. all the injectors were disconn...
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2000 Chevrolet Blazer LS 4.3L Misfire VIN: 1GNDT13W1Y
Hi Guys And thanks in advance. This vehicle has a random multiple mis-fire in all cylinders. A tune up was done at another shop. All the goodies were replace. I remove a couple of plugs just to check if they were wet and they were not, plugs nice and dry. I su... Trouble codes: P0300 (multiple miss-fire)
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2001 Chevrolet Astro 4.3L Brake pedal hard VIN: 1GCDL19W51
Need a diagnostic procedure for hydroboost
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2001 Chevrolet Cavalier 2.4L Poor Idle Quality, Surge, Misfire, Poor Fuel Economy, MIL Lamp on VIN: 1G1JF52T31
Customer complains of surging when coming to a stop and poor fuel economy. I verified the surge/misfire at idle in P/N or D/R in service bay and during test drive. Also power is good and car has no driveability issues off idle. I checked the fuel injectors wit... Trouble codes: P0201 (Cylinder 1 Injector Circuit Fault), P0108 (MAP or Baro Signal High), P0300 (Random Cylinder Misfire), P0440 (EVAP Emissions System Fault)
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2001 Chevrolet Silverado 2500 HD 6.0L Flexplate VIN: 1GCHK24U41
Vehicle came in with a hard to pinpoint rattle in the bell housing area. After pulling the transmission, we discovered that the flexplate was cracked in several places just inside of the ring gear. 18 months later, the truck comes back with the same sound comi...
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2002 Chevrolet Tracker LT 2.5L 4wd VIN: 2CNBJ63492
4wd light flashes randomly when in 4wd at stop sign it acts like engages some times but when you take off slight klunk and kicks out of 4wd ratchet noise like diff not fully engadge does engage when testing on hoist. does pcm turn on or off 4wd light from pres...
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2002 Chevrolet Trailblazer LS 4.2L Actuator VIN: 1GNDT13S92
The actuator on the front differential was replaced a few days ago at a different shop here in town. You can hear it moving in and out when trying to go into 4whl drive. All the dash lights appear to operate normally and shows it being in 4whl when you hit the...
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2002 Chevrolet Blazer LS 4.3L Stall, Misfire, MIL Lamp on VIN: 1GNCS13W52
vehicle come in w/ customer complaint of missing -rough running stall, after looking undr the hood i automatically noticed the plug wires jumping everywhere. i replaced the plug wires and the vehicle runs rougher. i looked at the distribitor cap and rotor both... Trouble codes: P0101, P0327, P0335, P0341
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2003 Chevrolet Blazer LS 4.3L rear differntial VIN: 1GNDT13X03
on deaccelleration vehicle sounds like driving over rumble strip without vibration ,no noise on accelleration,sound eminates or echoes from driveshaft on lift.vehicle has rebuilt transfer case and swapped out known good driveshaft and did not change noise ,fou...
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2004 Chevrolet Impala 3.8L Excessive Emissions, Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, MIL Lamp on
hi guys 04 impala keeps setting maf code when this acts up i during warm up prosses found coolant and air temps read ok but when it acts up fuel trim goes to -41 and o2 goes rich but maf is reading accordingly this one has me stumped when it acts up idle jumps...
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2005 Chevrolet Silverado 1500 HD 6.0L Speedometer VIN: 1GCGC13U25
This customer complained of the speedometer reading too slow and lower than expected power when towing his 3000lb trailer. I used the TECH 2 to check the tire size calibration figuring that would affect trans shift points. The scanner showed no tire calibratio...
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2006 Chevrolet Cobalt SS 2.0L MIL Lamp on VIN: 1G1AP14P26
Hi,This Cobolt has a 2L. supercharged engine.Vehicle arrived at my shop after having a catalytic convertor and Bank #1 Sensor #2 replaced at another shop because previous owner had removed original catalytic convertor.Trouble code P0141 was current code.Diagno... Trouble codes: P0141 (Heated Oxygen Sensor Bank 1 Sensor 2)
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2007 Chevrolet Impala LT 3.5L Transmission VIN: 2G1WT58K17
This is so weird. Need to know it any one had this happen to them or mite know how this would happen. Car came in for engine light check for codes, found code for large evap leak. Used smoke and found vent valve not closing. Ordered part and got next day. Inst...
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2001 GMC C-Series Topkick C6H042 7.2L No Start VIN: 1GBK6H1C61
Crank no start when engine is warmed up. Starts OK when cold. The engine will start on Starting fluid then runs fine. In the past this truck would lose power at highway speeds. If you shut it off and restarted it, it was fine. It had DTC164 indicator #2 and we...
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2001 GMC C-Series Topkick C6H042 8.1L MIL Lamp on VIN: 1GDK7H1E11
These sensors are available from dealer only and cost about 175 bucks ea. and they dont have same part number . Please help . Thank you . Trouble codes: P0332 (Knock Sensor 2 Circuit Low), P0337 (knock sensor 1 circuit low)
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2001 GMC Savana 2500 5.7L ABS Module VIN: 1GTGG29R81
Van brought in from another shop. Complaint was poor stopping and ABS function and pedal feels funny. Verified complaint, at 30mph on slight downgrade moderately applying the brakes results in intermittent rear wheel lock and lack of stopping. Pedal does not r...
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2001 GMC Sierra C3 6.0L transmission VIN: 2GTEK69U51
hey guys...owner brought this c3 to my shop on a rope. he says he was driving along back road, slowed for an intersection, and when he tried to accellerate there was no go. actede like tranfer case was in neutral. says trans has been to atrans shop twice recen...
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2005 GMC Sierra 2500 HD SLE 6.0L Misfire VIN: 1GTHC24U05
Hey, can use some help...got this 2500hd pickup with a p0300 random misfire code that only appears when you drive above 60mph,but it runs good. Has ac delco plugs(new), new delco wires ,cleaned injectors with GM stuff.Did power balance and injector tests with ... Trouble codes: P0300
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2003 Hummer H2 6.0L Headlights VIN: 5GRGN23023
I know this is probibly an easy fix for someone, how do you set the headlight horizontal aim, I can get the vertical adjustment correct but not sure on the horizontal on this vehicle. Jim in Quincy CA [...]
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1999 Pontiac Montana 3.4L Cooling Systems VIN: 1GMDX03XD1
A customer brought in a 1999 Pontiac Montana with bad intake gaskets leaking both anti-freeze and oil to the outside. Replaced gaskets - with new bolts. Also replaced thermostat, plugs and 02 sensor. Bleed cooling system and had heat in front and rear. Came ba...
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2001 Pontiac Bonneville SLE 3.8L MIL Lamp on VIN: 1G2HY54K81
Hello all, This Bonneville sets a P0420 converter code randomly. It typically happens at idle. It first came to me with an aftermarket converter that was very small. I connected my scanner and monitored fuel trims and watched the Upstream and downstream o2's. ... Trouble codes: P0420
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2002 Pontiac Grand Prix GT 3.8L Misfire VIN: 1G2WP52KX2
Hello all, Thanks for reading my request. This car came from a referal from a local (Reputable) trans shop. The owner is having problems when the car is warmed up and trying to pass other cars on the highway. At that time the complaint is a miss. The trans sho... Trouble codes: P0300
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Fixes & Summaries for GM
Fix/Summary Answers
1993 Buick LeSabre Custom 3.8L headlights VIN: 1G4HP53L1P
WELL YOU GUYS ROCK AS ALWAYS. WITHIN 2 HRS I HAD THE ANSWER. MICHAEL AND DANIEL HIT IT RIGHT ON THE HEAD. THERE IS A HEADLIGHT CONTROL BOX ABOVE THE PARK BRAKE LOCATION THAT HAD A BAD RELAY IN IT. THE ONLY PROBLEM IS GM HAS DROPPED THE REPLACEMENT PART AND THE...
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2002 Buick Rendezvous CX 3.4L engine light VIN: 3G5CAO3E12
Thank everone who sent responces, this one was different for us . The pcv valve was replaced before we got the vehicle and it passed the rattle test but it was the cause of all our headaches. i called the customer this morning to check how things are going ...
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1998 Chevrolet S10 2.2L Battery VIN: 1GCCS1940W
Alright!! Thanks for your help!! It ended up being a Body Control Module that wasn't shutting down. BTW, that 175ma draw never went away even after about 50 minutes or so. New one shut down in 20 minutes!! Well, not as low as I liked, but it was down ...
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1998 Chevrolet Blazer 4.3L Trans-Case VIN: 1GNDT13W2X
At this point the customer has decided to get a second opinion. I feel it may also be in his best interest as we are not 100 % sure . he needs the vehicle back ASAP and I can not make that happen for him. After he gets the second opinion I will follow up unde...
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2000 Chevrolet Malibu 3.1L Stall, FUEL PRESSURE DROP VIN: 1G1ND52J5Y
Thanks for all the help, found #6 injector leaking, replace injector and pressure holds now.
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2000 Chevrolet Cavalier Z24 2.4L Stall VIN: 1G1JF12T4Y
All of the replies i got were great, but because there is no fuel pressure test port on this vehicle and i don't have a low amp probe to check fuel pump current draw i couldn't do any further testing on the fuel system. Then the customer decided to trade in th... Trouble codes: P0171, U1016.
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2003 Chevrolet Impala 3.4L passlock VIN: 2G1WF55K13
thanks for all the replies. sorry for the delay in the closing. I had the vehicle towed to the dealer.(not somthing i like doing).they re flashed the bcm with the gm scanner. (i only have the snap on motius). they also said that they hade to replace the fuse b...
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2004 Chevrolet Silverado 2500 HD 6.6L MIL Lamp on VIN: 1GCHK24154
Thanks to everyone who responded. Terry hit it on the head! The wiring harness at the FICM had rubbed through two wires shorting them to ground we repaired them and insulated the harness with heater hose to avoid this again. The customer is very happy. Thanks ... Trouble codes: P0700 (Trans control system fault), U1800 (lost communication with FICM), U2104 (CAN bus reset counter overrun), U2106 (Lost communication w/trans control system).
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2007 Chevrolet Suburban 1500 LT 5.3L ignition VIN: 3GNFK163X7
THANKS TO ALL WHO REPLIED. HAD MANY GOOD IDEAS. HOWEVER THE CUSTOMER DECLINED FURTHER DIAGNOSIS WITH THIS PROBLEM. HAD A RELATIVE WORKING AT A DEALERSHIP. DECIDED TO PAY A TOW BILL ON VEHICLE. FINALLY HE HAS SINCE RESPONDED BACK. TELLS ME IT WAS THE BODY CONT...
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1996 GMC K1500 Sierra SL 4.3L Excessive Emissions, Poor Idle Quality, Hesitation, Stall, Misfire, Poor Fuel Economy VIN: 1GTEK14W0T
thanks a million every one. so it turns out that there was a small dent in the bottom of the fuel tank that wasn't visible due to the plastic cover attatched to the tank. with the sending unit out of the tank slightly, the pressure was normal. as soon as the s... Trouble codes: P0300.
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2001 Oldsmobile Aurora 3.5L Drivers door controls, DDM VIN: 1G3GR64H61
Ok, most of the replies I got said to check for broken wires in the door jam harness, which I did. All ok. I did have power and grounds to the DDM as well. I tried a used DDM and it worked sporadically. Some times it would work with the key on, but a soon as y...
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1999 Pontiac Montana 3.4L Misfire VIN: 1GMDX03E2X
Thank you for all the replies. The problem appears to be a valve timing problem. Inspecting the vacuum scope pattern shows #1 cylinder vacuum timing out about 3 which might be enough to cause a high rpm misfire. Thank you for the info on testing piston height... Trouble codes: P0300 (multiple misfire detected).
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2003 Saturn LW300 3.0L Misfire VIN: 1G8JW84R13
Ok guys it's true. The tough ones are always something stupid. Vehicle came in with # 4 misfire code and multi miss codes. Found that Saturn loves it's original plugs, Can not use after market plugs, must use original oem plugs. Installed new plugs from Saturn...
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