ok i have a 97 gmc jimmy with 150000km (93250miles)and in any temp you jump in to the thing and as soon as i put it in drive a give it some gas i the thing boggs like i am driving a 4 cylinder and i let of and once i get rolling it will run fine and wont bog out on me. i tryed some fuel injector cleaner and it helped it when its warm but not starting out and i am absolutely stumped on what is going on can any one help me

 

Could be your TPS (Throttle Position Sensor).

 

It is possible that you have water in the fuel. See what happens if you run a bottle of Iso Heat (red bottle) in the next fuel tanks of fuel.

 

i think i fixed the problem its not fully cured but i took my friends 00 s10 zr2 for a drive and all the new 4.3l vortecs seem to bog a little bit but mine was still worse

i cleaned the map sensor (there was a little bit of dirt in the sensor) and that has seemed to fix the problem.

thanks everyone for there feed back

 

I have a 99 and it was falling on its face bad i replaced the fuel pump and that fixed it (just a thought)