Hi everyone I am new here. I just purchased a mint condition 2000 GMC Jimmy SLE 4.3 4x4 the truck in mint no rust no scratches and has slightly bigger rims and tires. Anyways When I put the car in park and accellerate hard the car sounds like its back firing and it shakes and it revs up and down then will stall sometimes. When I'm driving it I cannot pass anyone and I loose power if I try to push the gas pedal to the floor... Anyone had this problem the distrubutor and plugs are new as well as the fuel pressure sensor the oil coolant and other fluids are all a1... The tachometer does not work on the truck except when its first turned on in the morning and it only seems to do this when its been on for a little while. If I drive gently its fine. I am pulling my hair out at this. I cannot figure it out first I thought it was the transmission but the motor does this in park too. Any ideas on simple things I can check I'm kinda new to all of this. Other than this I love my new truck! The truck has 250k kilometers on it
Thanks

Zachary MacLellan

 

Hey Zach

I think I have a similar problem as yours. The truck feels like its bucking, but only at a certain point. When it shifts from second to third gear, and between 2600-3200 rpm, it starts to buck. My guess on it is that it slips going into 3rd gear and then shifts back down to 2nd, but keeps trying to get into 3rd gear. The tach goes back and fourth when this happens as well. When I accelerate a little slower or a little faster it does fine though, it's just happening between that rpm range and I have never felt it anywhere else but there. Anyone else got some help?


Edit: Also, It's a 2000 Chevy Blazer LT 4x4 with 190k miles.