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1991 Buick Park Avenue 3.8L No Start
No start when cranking No spark from coil pak-will not fire STS tester. _has injector pulse when cranking- cranking RPM on scanner showing- -replaced coil pak - still no spark -replaced crankshaft sensor- still no spark -disconnected cam position sensor- stil... Trouble codes: 41 (Cam position Sensor).		 View
2000 Buick Century 3.1L most grids
GOOD EVENING...30 years in the business...20 with GM...never seen this before...I am a teacher now AT LINCOLN TECH IN NEW JERSEY...each grid line of the rear defogger [except for the top 2]..are melted [burned] right in the middle of the glass...as stated the ...		 View
2001 Cadillac DeVille 4.6L Engine
Vehicle came in with overheating concern from the customer. We found a coolant leak at the thermostat and coolant recovery bottle. Repairs were made to both items, and this corrected the coolant leaks. Before coming to our shop, this car had been worked on at ...		 View
2004 Cadillac Escalade ESV 6.0L radio amplifier
vehicle came in with a complaint of battery dies overnight. traced electrical system to the radio amplifier fuse located in the underhood fuse box. if the fuse is removed the draw is completeley gone. if the fuse is then re-installed the draw remains completel...		 View
1991 Chevrolet Corsica 3.1L No Start, Poor Idle Quality, Cuts out, Stall, MIL Lamp on
Hello to everyone. Got a good one for the GM guys out there. 91 corsica came in stalling, running rough and a MIL lamp on. Scanned and found prom error code and ect error. replaced defective ect and computer with a unit that had the updated prom. Customer took...		 View
1991 Chevrolet Lumina 3.1L Excessive Emissions, No Start, Poor Idle Quality, Surge, Cuts out, Stall, Misfire, Poor Fuel Economy
will not idle , off idle seems ok , if you rotate the key back just far enough to disengage the starter and hold it , it will run fine , but does not have power to all the sysytems in the car when you do this , i suspect ecm but not sure , have checked all the... Trouble codes: 45 (running rich).		 View
1992 Chevrolet Pickup 4.3L Hesitation, Cuts out
This is my first time asking for help please take it easy on me. This truck belongs to a co-worker's son(He's the oil change & brake guy), my boss is limiting my time on it. The truck will run O.K. sometimes, then when you start to accelerate it cuts out and b... Trouble codes: 43 (ESC moduleKnock Sensor).		 View
1998 Chevrolet Pickup 5.7L Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on
Ok another head scratcher at least for me. Customer came in complaining of a stumble but no codes and the truck sat for about a week. When i first looked at it it had no codes and seem to run fine, no stumble or missfire. (Keep in mind the motor was still cold... Trouble codes: P0131 (O2S Circuit Low Voltage Bank 1 Sensor 1), P0151 (O2S Circuit Bank 2 Sensor 1 Low Voltage).		 View
1998 Chevrolet Blazer 4.3L Transfer case, Differential
Hello! Having trouble with this blazer binding up in 4 wheel drive when turning. When in 2 wheel drive having no problems at all. When in 4 wheel drive and turning it will come to a complete stop, and has trouble moving. I removed both driveshafts and check un...		 View
1999 Chevrolet S10 Pickup 2.2L guages
hope someone can help. i have oil pressure guage working as well as volt meter but i have no fuel, temp, prndle, speedo, or odometer. all fuses are good. replaced cluster with used one same thing. any ideas?		 View
1999 Chevrolet Express 5.7L Excessive Emissions, Hesitation, Cuts out, Poor Fuel Economy
at idle this van runs great. engine will rev just fine on light excell, but med. to heavy excell it will not rev over 1200-1500 rpm. backfires through intake. falls flat on its face. fuel pressure in spec.koeo and 55psi when acting up. cam retard at 0- +1 degr... Trouble codes: P0131 (o2 low voltage), P0137 (o2 low voltage), P0151 (o2 low voltage), P0157 (o2 low voltage).		 View
2000 Chevrolet Tracker 2.0L Oil Leak
Attention Tracker techs. I have what appears to be a rear main seal leak in this tracker. I've already replaced the main seal and I sealed the crank bolts as instructed by several other posts I've found regarding this problem. My question is regarding a G.M. s...		 View
2000 Chevrolet Blazer 4.3L Hesitation, Cuts out, Stall
Blazer only stumbles at wot. You can easy in to it and at 1/2 throttle spins tires. If u wot it will sputter stall backfire what ever u want to call it. I say the pump is bad but it is 300$ so I want to be sure. Fuel pressure koeo 60-59 quickly falls an sta... Trouble codes: p0173 (lean), p0151 (lean).		 View
2000 Chevrolet Silverado 5.3L fuel gauge/odometer/message center/cruise control
inop. fuel gauge,odometer,message center, tech assumed cluster failure. replaced with o.e.m. reman. same problem, checked further & found cruise control fuse blown. replaced fuse & everything worked fine.test drove using cruise fuse did not blow.released to cu...		 View
2000 Chevrolet Impala 3.4L multifunction switch
left interior fuse box was replaced because of a "vehicle no start" turn key to start & got nothing, tap on the fuse box a few times & vehicle would start right up. loose contacts behind fuses. next problem: seems the blinkers do not work at all. when you try ...		 View
2000 Chevrolet Camaro 3.8L Radio, power top, power windows
This car has an intermittant inop condition where the radio, power windows and power top will quit working. If you hit a bump they may start working. I am having trouble on a wiring schametic finding things in common such as a relay. Has anyone seen this befor...		 View
2002 Chevrolet TrailBlazer 4.2L Ipc/Radio
This Trailblazer has been plaugeing me for weeks now. when the battery is dosconnected then the ammeter plugged in it shows no drain, the forst time it came in i saw it had no drain, sold a battery and sent it on its way. It came back 2 days later having had a...		 View
2002 Chevrolet Monte Carlo 3.4L No Start
Car will not start with key, Code P1626 will not clear and no communication with BCM at all. Checked connections at BCM, ignition switch and PCM. Have battery power at start relay but no ground from PCM. I can ground start relay and car will run for a few seco... Trouble codes: P1626 (Anti-theft system Fuel enable circuit).		 View
2003 Chevrolet Silverado 6.6L No Start
This Duramax has a no start when cold. I checked glow plug system and I have power to all glow plugs, and glow plugs tested ok. If you plug in block heater and wait a hour, its starts right away. By plugging it in I should be eliminating the fuel system and pr...		 View
2004 Chevrolet Express 6.0L Misfire, MIL Lamp on
i need some help with this one guys i have a misfire on all cyl it switches around have checked all plugs ok ran injector balance test cyl 1 55psi start 40psi after tested cyl 2 56psi start 34 after tested cyl 3 56 start 34 after tested cyl 4 56 start 34 after... Trouble codes: p0200 (inj circuit problem), p0300 (random misfire detected), p0155 (02 heater circuit bank 2 sensor 1).		 View
2006 Chevrolet Impala 3.5L Module Connector
Bought this car as a non-runner. I couldn't communicate with the ECM. After a lot of testing, I found a rodent had eaten the wiring harness in the air cleaner assembly that feeds both the ECM and the TCM. I can't finish repairing the harness because the genius...		 View
1991 GMC Pickup 7.4L lifters
hi guys, this 7.4 has got me. december 06 i bought this truck and drove it home to use the power train and chassis under my 1988 light 2500, i had the engine rebuilt by a local engine rebuild company. It ran fair when I brought it home, but seemed lazy. i had ...		 View
1994 GMC Pickup 6.5L vss circuit
I'm having a problem with a VSS circuit signal and was hoping someone might have run into a problem similar to mine. The vehicle in question is a Diesel 4x4 with a 4L80E trans. The spedometer along with the signal to the data link connector fluctuates above 60...		 View
1999 GMC Sierra 4.3L No Start, Cuts out
Two weeks ago this truck landed here not running.We pushed it in the shop and quickly found not spark from coil.The tech working on the truck put one on it and it started right up.We sent the costomer on his way the truck was brought back here on a hook 4 days...		 View
1998 Oldsmobile Bravada 4.3L Hesitation, Surge, Cuts out
This vehicle when hot , worse as it gets hotter, when slowing down almost to a stop and stepping into it will have a jerking as if it has cutting out ignition, vibration in driveline or other similar effect. The ignition misfire data reveals no misfire, there ...		 View
2003 Pontiac Grand Prix 3.8L Electronic
Hi All, I have this Grand Prix that is acting up. I initially diagnosed the vehicle and found a code P1811 (max adapt long shift). It had a customer complaint for long shifts. I replaced the pressure solenoid. Now after replacing the solenoid the transmission ...		 View

Fixes & Summaries for GM
Fix/Summary Answers
2005 Buick Century 3.1L security
HI I can call this car fixed to and extent My original cry for help on the theft system has been repaired as many of you suggested to fix the B2957 code was to change the Key cylinder and I did that and my theft code is no longer a problem but now I still hav...		 21
1994 Chevrolet Corvette 5.7L calipers
Thanks to every one that responded. It was the ABS pump that was locking the brakes down. After replacing unit all was well.		 17
1994 Chevrolet S10 Pickup 4.3L Delco Radio
First, thanks to all you guys for the help! The Fix: The radio was replaced with a new aftermarket radio/CD player supplied by the customer. The Delco radio was found to be internally bad (logic processor) and not repairable. With the help of the group, I disc...		 10
1996 Chevrolet Pickup 5.0L Control Head
Have already replaced the low speed resistor at the last head replacement. Found the coil on the relay pulling 4 amps. Install new relay to find it pulling 2 amps. Hope this is the culprit. Installed another new head & system is operating good. Thanks for all ...		 7
1998 GMC Pickup 4.3L Engine
I have finally had an op to remove the drivers side head, I did not find the piece of ceramic, although the shape of the missing piece was imbeded into cylinders #5 and #1. I also saw evidence of something else, a very small piece of metal 1mm X 1mm approximat...		 27
2002 GMC Envoy 4.2L transfer case
Thanks to all who replied..The fuse trick worked (so far) this is my wifes truck so as for now the system is working good, I just pulled the TCCM fuse with the [...] on,replaced it and the system woke up and has been working good...Thanks Again this site is Awes...		 11
2004 GMC Sierra 6.6L Misfire
no codes but found injectors 4 and 5 missfiring customer said to install 8 in unit and get it over with he ordered an 09 ford cause he has had too many issues with the duramax and the local dealers not wanting to warr...		 4
1997 Saturn SL2 1.9L No start
Replaced crank sensor and all is well again. Thank you all for your time once again		 16
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