2002 Ford Focus Zetec 2.0L Diagnosing P1406 and P0172 Fault Codes with Engine RPM Issues

Model: 2002 Ford Focus Zetec 2.0lts Fault Code: P0172 Posted: 2016-12-27 20:49

My 2002 Ford Focus Zetec 2.0L vehicle runs normally most of the time, but occasionally experiences engine failure. When this occurs, the engine RPM spikes unexpectedly to around 430 rpm. I have checked the OBD-II diagnostic system and confirmed the presence of fault codes P1406 and P0172. These codes indicate issues with the fuel system and air-fuel mixture, potentially leading to performance instability. I am seeking advice on possible causes and solutions for these specific fault codes in my model.