I have a problem. I have had an Engine code 36 for approx 4 months. The car used to backfire and stutter when I accelerated to 4000 rpm them run fine when it got to 4500 rpm. I took it to a mechanic and the car stopped the stuttering problem but the check engine light would not go out. I then put the turbo on the car and this problem resurfaced. So right when I get into boost the car backfires and slows. My Air fuel ratio gauge does not say that I am running very rich. I don’t have the ETG hooked up yet. Any ideas? TIA

HRC Stage 2
JE Pistons
Crower Rods
Port & Polished Head
3 Angle Valve job