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Could you elaborate on what you mean by the cruise control "pulsing"? Is this related to controls or performance?
Thank you for the explanation.
When the actual driving speed is higher than the set speed, the current to the Actuator flows from TERMINAL 11 of the ECU --> TERMINAL 7 of the Actuator --> TERMINAL 6 --> TERMINAL 12 of the ECU. This causes the motor in the Cruise Control Actuator to rotate to close the throttle valve and return the throttle cable to decrease the vehicle speed.
So, we're either looking at a bad ECU or most probably a bad Cruise Control Actuator to be the cause of this speed variation - if the engine is otherwise working OK, I would suggest replacing the Cruise Control Actuator. A Techstream or equivalent scan tool would have to be plugged in to analyze cruise control system data to confirm this is indeed the issue.
Please let me know if you have any other questions.