Cruise control will not disengage in deceleration and coast button triggers acceleration revving levels in excess of 3,000 rpm. No attempts will cancel, turn off cruise control such as hitting brake etc. will disengage the acceleration "rage". Finally throwing the car in neutral and continually pressing brake and shifting car back into drive mode stopped the problem. Multiple occurrences have been experienced on open highway and particularly when accelerating up hill and on descent that acceleration will not adjust speed.