What does OBD code P0420 mean for Ford?
What does OBD code P0420 mean for Ford? P0420 Ford. OBD-ii Code P0421 definition: Basically this means that the oxygen sensor downstream of the catalytic converter on bank 1 is detecting that the converter is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system. Symptoms Sumptoms of OBD code P0421 You will likely not notice any... Why is this 2004 Ford F-150 setting a p0174 Bank 2 lean? Come along as we look into why this 2004 Ford F-150 is setting a P0174 Bank 2 lean. My Company BSG Automotive...