fuel trim.bank 1 error

Question

engine management light on fuel trim bank 1 error. have a tdi plug n play chip installed k and n air filter installed and ecotek valve on crankcase breather would any of these cause that fault.

Answer 1

This code can be the result of a faulty front O2 sensor, a vacuum leak, it's possible that K&N filter is causing to much air flow so the system is lean.