I was cruising down the highway towing the boat a couple months ago, set cruise on 60 and just started to slow down nice and easy. Since then, it has been out except I tried it yesterday and I feel it trying to take the pedal but it gives up. I am looking for any suggestions on an accurate way to diagnose if it is a vacuum leak or something in the servo. I look forward to your response.

I hear the servo under the drivers side battery takes some abuse from the battery location. I think if mine had one I would start looking there.