I have a prm intake t1r test pipe and his car back along with jrt maf sensor and my car has a check engine light shining bright. I bought the weapon r cell defouler but it doesn't work. Still see the light. Is there an insert that I put in the L pipe defouler to correct the A/F ratio for the o2 sensor?

 

I used a straight style anti fouler with my Weapon-R header and the CEL only came on twice for P0139 (voltage low - car thought the cat was there but the sensor was bad). The angled anti fouler never worked for me.

 

I have the angled fouler on my Weapon-R and the same code comes on once in a blue. But for the most part mine works. It's a fickle thing, I wonder if a tune would help?