04 Grand Prix GTP hi speed miss under load

mikegust

New member
Joined
Feb 6, 2022
Messages
1
Reaction score
0
Points
1
Hi all.
I have an 04 GTP.
It always had a problem where at operating temperature only, it misses and bucks whn trying to accelerate from highway speed.
Doesn't do it cold, amd gets progressively worse as engine temp rises.
Recently swapped in a complete used engine and transmission......same problem.
Have replaced cat, all 3 coils, fuel filter, plugs, wires and a good used icm.
57 psi of fuel pressure at idle.

Any ideas ?
Thanks in advance.
 
Back
Top