Can a fues or relay on the cruise control cause engine revving after starting

Engine speed being high after starting is likely related to a vacuum leak or air intake issue. It will need checked out for that. Regarding your odometer and speedometer, do you have a digital dash, or a conventional one? If It's digital, it could be an issue in the cluster itself. If it's a conventional dial type, you'll need to look into a possible speed sensor issue, or related to the wiring or gear that drives it.