The other day I noticed while I was driving that my car farted or kinda backfired bettween gears. I have a 04 auto with an uppipe, shorty dp, ic hoses, aps bpv and a borla hush cat back. What could be the problem? It only happens at WOT or when I rev the engine and not everytime. Any help is appreciated!

 

BOV, makes you run rich when shifting.

 

aps isnt a bov its like stock bpv, plus I dont have enough power in the car to make blow off.The aps is made to recurculate but I will put on the stock bpv and see if that does it.

 

it's a turbo car, backfire does happen with mods, get used to it (my 06 backfires with just a 3inch catback straightpipe at wot or low rpm's sometimes)

 

if you are catless it will make happen more often, but yes, when you put a big dp on a the suby it will start to backfire a little bit. Put a SARD R2D2 on and youll shoot flames.

 

ok, I do still have one of the three cats still on. it just scared me a little bit when I herd the noise, didnt want to blow up my car!