VEHICLE: 1996 s-10 blazer


THE ISSUE: at any rpm above idle, it wants to misfire, BAD, to the point its hard to get the rpms any higher once its started to act up(usually around 1500rp).
Idles fine.
If i try to get the rpms higher(usually flooring it) as soon as i let off the gas, as the rpms go down its smooth, so i can go to 3k and it will return to idle without a problem. This is all in park. No load
It first started all at freeway speed, out of nowhere causing me to pullover and limp home at idle.

THINGS IVE TRIED/new parts:
I have another blazer(running condition) same year so i swapped some parts:
Pcm
Coil
Maf

New parts:
Distributer and all ignition parts(less than a month)
Fuel pump(about 2 years)

Fuel pressure is about 58 at idle, goes to 62ish when trying to raise rpms
I know thats slightly below standerd, but not sure if thats enough to cause the problem
Any and all help is appreciated
Thanks

 

Try check catalytic converter. If you have oxygen sensor before cat take it out and make sure to deflect exhaust gases with something metal if pointed toward items that can burn or melt. If RPM goes up to say 4000-4500 fast then you clogged cat. Note CEL will probably light up you will need clear it when done with test.

 

exactly what I was thinking as well. clogged cat!