need help my car at 4rpms it boggs and exhaust pops alot like its clogged what can it be my computer is chipped and it should redline at 7800 and it dosent go past 7 i dont have a cat im straight piped so cant be that??its a d16z6

 

Have you checked the ignition timing and the plugs, wires, cap, ans rotor?

Any CEL codes?

 

not yet happen tonight in the morning so check those things?

 

check engine came on but then dissapeared why could that be?

 

You can't guess the codes so you need to pull them.