I just bought a used GMC Envoy it has the 4200 engine and has 78000 miles, is it ok to start using synthetic oil or will this do any damage?
I have a 96 GMC 1500 2wd with the 4.3L v6. When I come off of a stop sign and give it about half throttle the truck shakes really bad right before shifting into second. I checked the ATF and it was a little low but adding some did not seem to solve the problem. The shaking only occurs when giving it somewhat hard gas off of a stop sign and all the other gears shift fine. I also note that there is a thunk when I shift it into reverse. The shaking seems to be in the front but it is hard to tell. Could this be something as simple as a u joint or do I have bigger problems?
I have a 2001 GMC sierra 1500 8cyl 5.3L. When i am speading up slowly, just crusing, are climbing a hill it will start hesitating kind of bad. I have already changed the plugs and wires. What else could cause this.
I have a 1997 GMC Yukon with 160k on it. When I start the truck in the morning, I get a nasty hesitation that will almost throw you out of the driver seat. The hesitation continues while driving. I take my son 5 miles to school and leave the truck off for 10-15 minutes. When I drive it to work (after dropping my son off) the hesitation is nearly gone. If a smooth engine is 100% and a stalled engine is 0%, my engine’s smoothness on the first drive is 25%. After the 10-15 minute off period at my son’s school, the engine’s smoothness is 80-95%. The engine remains smooth for the rest of the day (when I drive home after the truck sitting for 8 hours). Also, on the first drive (25% smoothness) the engine temp will work up to 200 degrees. Subsequent drives, the engine temp sits around 150 degrees. If I idle the truck for 15 minutes in the driveway and then turn it off for 5 minutes before I leave for my son’s school, the engine smoothness is 50-80%. The following work has occurred before the hesitation started: rear freeze plugs, rear main seal, ignition module, pick-up coil, rotor, and cap. After the hesitation started, it has got a fuel filter, new plugs, and new plug wires, water pump, thermostat, and temperature sending unit (none of which has helped). The truck is throwing O2 sensor codes but it has been doing this for the past 5 years. Thanks in advance for your help.
My 99 jimmy with 230 klms/170 mi. started knocking and it sounds like it’s coming from the top rear engine area, had it to several mechanics that say its a ristpin, or collasped lifter. I have the lifters out now and they all look good , should I just replace them or can I test them some way to see if that was the problem. I’m stuck not knowing my next step.
On a 1988 gmc S-15 pickup with a 2.5 engine, I’m getting good fuel pressure to the carb and power to the fuel injector, but it’s not injecting fuel into the carb. Am I safe to assume that I’ve got a bad injector? What’s puzzling me is that when I apply 12 volts directly to the injector, I do hear a “clicking” action!
I was spun around on a snowy road and while sliding hit dry concrete. my vehicle jolted and the steering wheel locked up. now its stuck and hardly moves at all. I tried changing back to two wheel drive and then back to four but still nothing. When i back up it steers right and when i steers left..
my friend just bought a 2008 gmc sierra and the alarm keeps going off and the truck is pretty much in shut down. cant start it cant do anything. we’re trying to figure out how to fix this problem. we arent sure if its because of the key fob? we tried putting a new battery in the key fob, still nothing. when you go to start the truck it wont even turn over and the alarm keeps going off. also the key fob only turns on but doesnt actually do anything.
i have a 1995 sierra 2500 series 5.7 gas engine. my horn and my washer fluid arent working. i cleaned all my ground posts. put in new fuses. wen i hit the horn you can hear the relay switch clicking. and when i first went to use the washer fluid it squirted once then stopped. i took out the horn and the pump hooked them up to a battery and they both work. i cleaned all my ground posts with no go. any clues???
The Chilton’s manual for the range of trucks that includes mine includes a wiring diagram that is supposed to be year specific. This diagram shows a fuse panel marked ‘Horn’ under the relevant slot, when the stock fuse panel is, in fact, marked ‘Horn/DM’. What does the ‘DM’ refer to, and more importantly, what all is served by this fuse??
I’m chasing a short that has this fuse apparently directly affecting the operation of both my fuel pump and my dome lights that I’m aware of at this point. This short is probably the direct result of wire overheating due to a much nastier short in the rear loom that I just repaired.