Nissan Repair: Cruise Control, cruise control module, continuous cycle

Question
On my 91 Maxima SE with manual transmission, if I engage cruise control between 65-70 mph, car will rapidly decelerate 10 mph/accelerate 10 mph in a continuous cycle until I cancel or brake.

Answer
Michael,

If the speedometer is accurate and is working properly then the problem would be with the cruise control module that connects to the throttle via a cable.  Follow the cable from the throttle to the black plastic and metal box and that is the part that needs to be replaced.