He's the situation. I take the car out for a hard run and when I get into 3rd, and,4th gear the car does not want to go anymore even when I press on the gas it just stays at a certain rpm. I thought it was the fuel pump and i changed it to the walbro 255 and it still does this. Could i be leaking boost?, O2 sensor(I am running just the downpipe with no o2 sensor) I will get it fixed but not now.

By the way I am running a Greddy turbokit, on an 95 Ls with the blue box.

 

I really need you guys help!!!

 

what is this certain rpm? and it only does it in 3rd and 4th, not in other gears? it would be totally wierd if it just stuck at say 4000rpm and never moved above that no matter what you did. I'm sorry i can't help much. maybe someone here could.

 

It does not stay there for good but it just does not want to go

 

put the o2 back in....pretty sure thats the problem.. same thing happpend to me

 

sounds like it could be ignition related. Try replacing the plug wires, plugs, and check the distributor cap/rotor for wear.

 

Problem fixed it was the O2 sensor