GELewis

The cruise control on my '94 968 Cab works intermittently. I've replaced both the servo and control unit, but the problem persists. Any ideas what else might be the problem?

plumbum

Did you replace the parts with new ones? Also how is it intermittent...if it works and quits I would look at the brake switch, if they were old parts I would do a search there are a few fixes...I did the re solderer of my control module and now my car accelerates most of the time when trying to "Set" the cruise...Next stop will be the servo.

mytrplseven

These things have a mind of their own. My computer would only work on certain speeds. Replaced it with a new brain and worked on the solder joints on it and the servo. The odd thing is, it works great until heat builds in the engine compartment and then you can't turn the thing on. If it's working before the engine compartment heats up, then you're good to go. I think I need to examine the servo unit for heat sensitive components.

Sysgen

Something I've always wondered, how do you set the cruise? It never worked on mine but I'm curious how you set it if I ever fix it.

You push forward to set, pull to cancel? Up and down to adjust speed?

mhr

Exactly

One cool feature if you push the clutch and change gears it will actually blip the gas

catamount

Correct, you push the stalk forward to set the speed, pull it to cancel, push down to resume (or reset in Porsche vernacular).

BTW, here's a link to Clark's Garage info on cruise control, http://www.clarks-garage.com/shop-manual/elect-04.htm

gregeast

I've had some luck cleaning the conducting strips on the servo unit, as outlined in the Clark's Garage procedure above.

Pay attention to how the servo goes together when you take it apart, I didn't and scratched my head for a long time before I figured it out...

GELewis

I cleaned the contacts and lubricated the original servo per the instruction in Clark's Garage and when that didn't solve the problem, I purchased and installed a servo that someone else had prepped and tested. I replaced the original control unit (all the solders tested good) with a second one that had been refurbished, and again, that didn't solve the problem. Next I'm going to replace the switch on the brake pedal (though that doesn't seem to trigger the problem), and clean the contacts in the steering column stalk switch. Does anyone have any other ideas?

Sysgen

Mind blown!!! Sweet, I'd like to try that

That's where I'm at also. A couple of years ago I purchased a used column stalk from someone here and when it arrived it was broken, so I gave up trying to fix it.