Category Archives: GMC

GMC truck repair questions and answers. Expert mechanics offer free help, information and advice.


GMC Envoy P0894 Slipping transmission

P0894 code I have 2005 GMC Envoy. I already changed fluid and filter when driving it will shift in 1st and 2nd fine then when gets to 3rd it will just idle real high like it’s in neutral. I have to keep giving gas and letting off until it hits gear. Is my trans shot or what all may it be? ANSWER: P0894 code is a…

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1991 GMC Sonoma baby gas pedal till up to speed

I have a 1991 GMC Sonoma, 2.8 liter TBI engine, 5 speed, 81,000 miles that bogs downs when you give it gas you can baby the gas pedal to get up to speed but its still not quite right. This is more severe in cold weather than warm but there is still some what the same problem when warm. This is what I have done…

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GMC Yukon SLT 2008 Struts

Hello. I have a 2008 GMC Yukon SLT that has a bad driver side strut. I purchased a set of Detroit Axle strut kits, but they don’t have the electronics like the OEM struts. Is it necessary to replace these with the electronic version or can a regular non-electronic strut be installed? They fit just fine, but will likely throw a dash light on if…

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GMC Safari Fuel pump vibrating loudly

I have a 1996 GMC Safari i changed fuel pump in the tank it worked fine for about 10 miles then it just died while going 30 mph and a loud vibrating sound came from the tank and car wouldn’t start. Everytime i turned the key forward that same loud vibrating sound happens. So i thought it was a bad pump so i replaced it…

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1500 GMC Has Fuel Pressure But Won’t Start

I have a 1994 GMC S1500 4.3 I t would shut down on me I was able several times to restart with either I replaced fuel filter fuel pump i and even ran direct power to the pump with an on/off switch the truck ran about 10 miles perfect than shut down like it had before i got it restarted with either got it home…

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2001 GMC Safari Coolant Leak and Rough Idle

Hello. My son has a 2001 GMC Safari with a 4.3 engine. He complained of a “rough idle” along with a coolant leak. Not knowing what the rough idle might be, I suggested he bring a new set of spark plugs. I listened to the engine then looked and found a bad left side motor mount, which I replaced along with the spark plugs. I…

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GMC Canyon Code P0116 Temperature Sensor And P0102 MAF

2006 GMC Canyon. When you push on the gas to take off it hesitates, while I am driving you can feel the engine hesitating, and when I slow down to stop it hesitates and the RPMs jerk and it stalls but if a pump the gas a little when it hesitates while I am stopping I can keep it from stalling. When I coded it…

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Warm Air From GMC Sierra Vents With A/C On

A/c compressor kicks on when ac is turned on, but no cold air comes out of the vents. You can change which vents the air comes out of. The ac is fully charged. When heat is on it only blows hot and can’t change to cooler heat. The vent output speeds can be changed. Any Ideas? You have a faulty temperature control actuator. There is…

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GMC Sierra A/C Clutch | Chevy Malibu Blows Warm Air

2000 GMC Sierra 1500 4.3 Vortec v-6. The clutch went out on my A/C unit. Do I have to replace the whole system or can I replace the clutch and bearing only? Will I have any freon leak when I remove the clutch and bearing? For now I have rerouted the serpentine belt to continue to use the truck. Answer: Depending on which type of air…

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1996 GMC Sierra Heat Defroster Controls Not Working

Live Chat I have a 1996 GMC 3500 Sierra 7.4 Litre. Battery cable came loose, arced and blew fuses. Replaced fuses and all was well. later, when I tried to turn on defrosters- I have absolutely no controls working at all (Heat/Defrost). Blower is running on high, but are cold. I have 2 buttons (AC and Recirculation)(Ext. Cab) and the lights in those do not…

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High Beam Indicator On The Dash Of My GMC 2500

Why is the high beam light on in the dash of my 2004 GMC 2500 pick up when the truck is off and the high beam lever is off. ProTech: You’re probably looking at a short in the headlamp wiring somewhere, or even possibly a faulty instrument cluster. Every thing else works fine. I just pulled the fuses and the really for both the high…

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1997 GMC Sierra Engine Light And Idle Surge

MY 1997 GMC SIERRA W/350 V8 HAS A DEAD CYLINDER ON #4. SPARK PLUG IS GOOD, WIRE IS GOOD DISTRIBUTOR CAP IS GOOD. WHAT ELSE COULD BE CAUSING THIS DEAD CYLINDER ? TRUCK HAS 117,000 WELL CARED FOR MILES ! ProTech: Have you tried a compression test? Not yet, but a compression test was next on my list. I would do that for sure. You…

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2007 GMC Sierra Burns Oil and Idle Problems

2007 GMC Sierra with 50k miles has started to use oil, could this be a PCV problem? There have been problems with oil consumption on those engines. Mainly a piston ring problem, but there is a service bulletin to attempt a correction before replacing pistons and rings, which is a big job. Do you have a number or date? Just a second and I will…

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2003 GMC Yukon Dash Gauges Not Working- Recall

My 2003 Yukon XL (Suburban) with 5.3 motor and 70k miles has no power to any of dash gauges. The truck runs and operates fine, but the radio, heater controls and dash lights work fine. No gauge activity at all. All gauges are at the zero mark. I believe I have checked all fuses at left hand corner of dash, under dash and the under hood…

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