My 2000 Civic EX cruise control recently started acting strangely. If I set the speed at 70mph, the speed will ramp up and down between about 70mph and 75mph. It won't stay set at the speed I want. The ramping up and down drives me crazy! It does it any any speed, since I tried it at lower speeds as well. Help?

 

Cruise control requires vacuum to work. You might have a vacuum leak. That's my best guess.

But, of course, if RonJ pops in, he'll say "Don't guess. Troubleshoot."

 

I visually inspected vacuum lines and they looked good.