My 91 NA Coupe did not come with cruise control and I'd like to retrofit it.
The Haynes manual is terribly vague about the components involved.

I already have the dash switch.

I've seen the actuator assembly on two cars in the junkyard- both are vacuum actuated, but have read that my year had electrical control.

So, two questions...
-What actuator do I need, and
-Is there a brainbox involved and if so, where is it located?

Thanks.

 

The Cruise Control unit on a non convertible is located just behind the interior fuse box. The plug is most likely already there. Look at the wiring diagrams and the plug in the diagrams and compare it to the one you find. The wire colors should match up.

The switch in the cluster surround should have a somewhat canted face on it to be a series five. A series four switch is more or less straight up and down face or squared off if you will. I"ve posted jpgs of the two items in the past.

Buy the electrical one. There is a WANTED PARTS section on this site. Advertise.

The parts just plug in and the actuator when you look at the cable .........well, it's intuitive on how to connect it to the throttle bell crank. Piece of cake.

 

The Cruise Control Unit has to be for a series five. The series four won't work. The plugs and pinouts are different. Only series five CCU.

 

Tell you what. This might help you decide.

I've a series four car outside with the electric actuator. I took the plug off the elect and connected it to the vacuum actuator( SPARES ARE US) and put a vacuum tube on it. I layed the cable on the windshield so I could see the end of it.

I drove the car at thirty mph at a steady speed and hit the cruise set button. The cable on the windscreen retracted. I touched the clutch pedal and it then extended.

What did I just say? I said on a series four car, the actuator can be either electric or vacuum operated. Just proved it.

Series five? Got me. Don't own one, but I'd bet the vacuum one will work for you if you can't get the electric one. They're worth maybe on the outside twenty bucks if not screwed up looking. Hacked up etc.