DTCs P0172 and P0175 System Too Rich Diagnostic Aids

WARNING: This page is about a different variant/trim than selected.

NOTE: If the system is rich at certain conditions, then the LONGFT PID would be a negative value at that airflow, indicating that decreased fuel is needed.

System rich concerns are caused by fuel system concerns, although the MAF sensor and base engine (for example, engine oil contaminated with fuel) should also be checked.