How would you troubleshoot to find out what needs to be repaired or replaced when the cruise control on a 1993 Ford Explorer Sport II works very internittently?

Answer 1

Fords/Lincolns have been known to display intermittent cruise operation characteristics that can be traced back to the ignition switch. If you've done some basic visual checks on all of the vacuum lines (no cracked or stiff lines or hoses), good vacuum pressure (remove one with engine running and put your finger over the hose and nipple it went to - - should feel the sucking), and related cruise component linkages are intact, then it might be that the contact in the ignition switch is worn to the point of a "hit or miss" closed position when the key is in the on/run position. A test for this, without alot of equipment, would be to jiggle the key in the ignition while driving and activating cruise. If it works after a jiggle, you've found the culprit. I've not replaced the switch in an Explorer - they're available at Auto Zone or your Ford house - but know that it takes a little effort to do. What ccan cause this is having way too many keys and doo-dads on your key chain. The weight of all those hanging extraneous keys and toys can cause the cylinder to wallow out the cams and lobes in the ignition key housing. We're not talking about the tumblers, but the actual part of the mechanism that is what we call the ignition cylinder and related switch inside the column. After a repair, and for your other vehicles, get one of those easy release key chains that allows you to remove all other keys you have on your keyring from your ignition key. The weight is simply too much for what the ignition key device is made to bare. - - Texavette