Ford P2439 OBD-II Trouble Code Definition: P2439 Secondary Air Injection System Air Flow/Pressure Sensor Circuit Intermittent/Erratic P2439 Ford OBD-II Trouble CodeDescription: OBD Trouble Code P2439 Secondary Air Injection System Air Flow/Pressure Sensor Circuit Intermittent/Erratic Sorry no other information,Please help us to improve,Any information is appreciated.Thanks. […]