Some 2011-2012 Ford F-Super Duty 250-450 pickup trucks equipped with a 6.7L diesel engine may exhibit a buzzing noise from under the hood while the engine is running and/or for up to 30 seconds after the engine is shut off. This concern may be due to the wastegate control valve vacuum harness causing the wastegate control valve to resonate.
1. Does the wastegate control valve emit a buzzing noise while the engine is running and/or for up to 30 seconds after the engine is shut off?
a. No – this article does not apply.
b. Yes – proceed to Step 2.
2. With the buzzing noise present, disconnect the vacuum hoses from the wastegate control valve. Does the buzzing noise stop?
a. No – this article does not apply. Proceed with normal diagnostics.
b. Yes – proceed to Step 3.
3. Replace the wastegate control valve vacuum harness.
a. Remove the throttle body
b. Remove the air cleaner outlet pipe
c. Remove three wire harness retainers and position aside the engine wire harness.
d. Disconnect the vacuum harness and remove.
e. Reverse procedure and install a new vacuum harness. The new vacuum harness is available as P/N BC3Z-9D430-E.