1998 Accord LX, 2.3L VTEC, 227k. Started having issues with the cruise control. It started out just fine, but about five miles down the highway it started accelerating, then decelerating, and fluctuating back and forth between speeding up and slowing down. I turned it off and tried it again about ten minutes later, but the same thing happened. Could this be the cruise control relay or wiring, or possibly the TPS?

 

Check actuator, vacuum lines and vacuum reservoir for leaks. This would cause erratic actuation of cruise control.

Vehicle Speed Sensor is another possibility. You would likely see erratic speedometer indications in this case.

Suggest obtaining a Honda shop manual which has all diagnostics necessary to trouble shoot cruise control. Try automanualsource.com for an inexpensive download.

good

 

The speedometer works fine. I'll check out the manual and see what I can come up with.