Some 2011 Ford F-350 vehicles built on or before 11-1-2010 may exhibit an audible clicking noise in the engine compartment and/or hard starting after refueling, with DTC P0144A, P0171, P0174, P0316 and/or P1450.

The problem may be the EVAP purge valve.

1. Does the vehicle exhibit an audible clicking noise in the engine compartment?

• Yes: Proceed to Step 2.
• No: Proceed to Step 3.

2. Unplug the electrical connector from the underhood evaporative emissions purge valve. Does the noise go away?

• Yes: Proceed to Step 4.
• No: Refer to the Powertrain Control/Emissions Diagnosis manual.

3. Is the vehicle experiencing a hard start after refueling with the afore-mentioned DTCs?

• Yes: Proceed to Step 4.
• No: Refer to the Powertrain Control/Emissions Diagnosis manual.

4. Replace the evaporative emissions purge valve located in the engine compartment. Refer to workshop manual, section 303-13.