Ford P0431 OBD-II Trouble Code Definition: P0431 Warm Up Catalyst Efficiency Below Threshold Bank 2 P0431 Ford OBD-II Trouble CodeDescription: OBD Trouble Code P0431 Warm Up Catalyst Efficiency Below Threshold What does the code mean? OBD-ii Code P0431 definition: Basically this means that the oxygen sensor downstream of the catalytic converter on bank 2 is detecting […]