i installed a greddy exhaust and berk hfcs had it like that for 6 months no problems with stock y pipe still on car. now my check engine light turned on 2 weeks after i installed a ichiba y pipe. dealer scanned the car told me its because of the aftermarket berks. berks have non fouwlers built in. what do i can. would i be loosing power... please help.

 

you shouldnt lose power with the light on just for the hfc.

 

I get that sometimes too, every couple of months. I don't have the y-pipe but a full Greddy cat-back exhaust. The code probably just reads that the emissions aren't as clean as they should be. That is why they said it was the berks. Sometimes I think it might be a touch of sub par gas. I reset the light and it doesn't come on again for a while. I think the cats are on the boarder of the emissions allowance window.

 

got you. anyone else have input please post up. thanks