Also posted this in the Daytona forum. When I got up to 40 mph, turned on the cruise control and pressed the set switch. Then I let off the accelerator and the speed started to drop. Looks like the cruise control isn't working. I checked the vacuum lines to the speed actuator and it is fine. checked all fuses with a meter and they're all okay. What else should I check? I really need the wiring diagram for it but I have the Haynes' 92 Shadow speed control wiring diagram. Will this diagram work for the Daytona too? Any help is appreciated.

 

Looks like it was a dirty electrical connector to the servo. Drove the car on the highway and it works fine.