Still running rich

[87ttsupra]

Ok so i put the stock bov back on and turned the boost down and im still haveing problems with it running rich and back firing every now and then. its not as bad as it used to be but its still bad right? how bad is it to run rich? the only thing i can think of is the O2 sensor. im getting code 21. theres so many problems with this car lol.

anyways... any help would be great thanks

 

[suprahilux]

need more info ie. what are you talking about.

do you have any mods? did it just do this suddenly? are there any codes?
need more info

also check for boost leaks!!!