Diagnostic Aids

An accurate indication of fuel level is required for PCM to properly pass or fail this DTC. Always diagnose fuel level sensor DTCs before performing this DTC test. Always check for fuel level sensor DTCs stored as history.

Perform physical inspection of EVAP system. Check the following items:

• Loose, missing, defective, or incorrect fuel tank cap.
• Incorrectly routed or defective EVAP system vacuum and vapor lines.
• A malfunctioning or damaged EVAP vapor canister.
• Check for charcoal release from EVAP vapor canister.