Tech Tips (by ALLDATA): Ranger cruise control unstable
Problem: The cruise control will not hold a steady speed and the throttle pedal is visibly moving up and down. The truck runs smooth when not in cruise control. No DTCs.
Details: The tech verified smooth VSS input to the cruise module, checked all cables for binding, all vacuum connections for leaks and the dump valve at the brake pedal. Replaced the servo assembly with another one from a donor truck – same problem. Tested all power and grounds to the cruise control module – all tested good.
Confirmed Repair: Replaced cruise control module and the problem was solved.