Just like the title say... when I turn on my cruise control the car starts accelerating and does not stop unless i turn it off.
Any idea where to start?

I have not looked at the adjustment pots yet, or tried my light setup but will be.

Thanks

 

Not sure if this is the same issue, but it might provide a place to start looking.
XKS Unlimited Tip

 

Here's some reading that might cover the problem

Cruise Control

Also, there's an adjustment to 'trim' the cruise control speed. It's on the cruise control module. My gut feeling, though, is the problem you're describing has something to do with one of the little valves in the cruise control servo assembly. The article linked above discusses the valves

Cheers
DD

 

Good catch, but that bushing was used on the later Hella cruise control. An '89 would still be on the earlier Econocruise system

Cheers
DD

 

Yeah, mine did that. The adjustment pots took care of it. If you're lucky that's all it will be.

 

I have rebuilt the cruise control system, so my fingers are crossed.
Pulled the cruise control module - there are two pots... which one to adjust?

Thanks for the links.. it seems the adjustment is very fine.

 

[Foggy memory disclosure here]

With the cover in place there should be a small port that makes one of the pots accessible. That would be the one to adjust.

Cheers
DD

 

The one on the left im front of the yellow box cap. While driving is best..turn it counter-clovkwise to reduce the engagement speed. A little goes a long way. It's a fiddly business..you need an assistant. if you go too far the cruise won't engage so you can verify that this is the culprit pretty easily.

 

I've read about the access port thing. Mine doesn't have one for sure. Maybe they added it later..or took it away?