Can anyone tell me hoe to do a Throttle body bypass on a 1999 4.8 vortec.
Thanx

 

i think it's the same as on my 02 6.0L. Look at the bottom of the tb, there is a hose coming from the radiator into the bottom of the tb and another coming out of the tb and into the drivers side engine somewhere. Not sure where. All you need to do is "bypass" the tb. ie, either just pull them both off the tb and hook them together somehow, or if long enough, run just one of the hoses from the radiator to the engine. make sense? be sure to clamp off the hose coming out of the radiator so you don't make a mess. also, make sure the engine is COLD. This mod is probably not even worth doing if you ask me. I did it cause my tb has been relocated because of the whipple and the tb cable was rubbin on the hose and causing it to leak.

 

thanks man yeah i also think its a waste for such little performance but i was just curious thanks for the help

 

Just get a 3/8"(think that was the size) barbed union and join them together, use the existing clamps.
Philip S.