|
You need a tune. Aftermarket headers almost all but require one, whether or not they're catted. That'll be the reason why you get an AFR imbalance and code since it deals directly with exhaust flow.
CAIntakes will also alter your AFR though sometimes not to the point of generating engine codes by themselves. Hit and miss at generating codes, but also questionable (if any) gains too.
The two combined is almost certainly what's causing the AFR imbalance, sort of surprised the dealer didn't note them at all..
OFT or Ecutek will get you sorted out.
|