Some 2008-2010 Ford F-Super Duty trucks equipped with the 5.4L engine may exhibit a MIL or wrench light, with DTC P2135. Various other DTCs may also be present. Drivability symptoms may include intermittent rough idle, idle speed below specification and/or reduced power.
The concern may be attributed to the TPS (throttle position sensor) hardware. Follow the steps in the workshop manual, section 303-14A.
The replacement TPS is available as P/N 6L2Z-9B989-D.