i posted this a couple weeks back and didnt get much info so ill try again.i have an 01 itr stock besides aem cai and a uni exhaust....my bumber and part of the spoiler is getting stained black really bad my buddy told me it was running rich he told me to pull a plug i did and the thread are very black and the tip is an ashy brown color....i tried moving the exhaust out from the car more and it didnt help any...the car has 31k miles and i bough it with 30k the plugs were replaced when i bought it i got it as a certified used car at a local acura dealership.i have the 100k powertrain and am afraid if i take it to the dealer they will fuck me by saying the intake and exhaust caused this and void the warrenty please help! i thought about an aftermarket fuel pressure regular and some dyno time or a more costly apexi vafc if nesscary?