Cruise Control Install - Part 1 - 08/31/2015

Cruise control is a luxury most modern cars come with (except Audrey's Sunfire). Having it is a beautiful thing as you can take long trips without worrying about how badly your foot is going to fall asleep. I decided that now is the time to install the factory cruise control setup on this car so I can cruise long distances.

A basic overview of the cruise control system.

The transducer and servo. The vacuum from the transducer on the left to the servo on the right with a T in it goes to the firewall and controls the throttle position. The right long hose on the transducer is engine vacuum (T'd off the PCV).

The firewall grommet feeds the electrical connections and the vacuum stop switch.

The cruise control stalk that goes in the column and the 2 brown plugs that connect to the brake switch to kill cruise if you push the brake pedal.

The 45 year old grommet is still pliable if a bit greasy and nasty.

Uh oh. We're missing the hole in the firewall to feed all of the accessories through! It's supposed to be right here:

There's a bunch of dimples on the firewall to indicate spots to drill...

Fortunately the firewall insulation pad tells all.

Plop out the piece of firewall insulation and you've got your spot to drill!

Not my best work. I don't have a hole saw so I made due with what I have. 3/8" drill bit x2 for the center and 3/16" for each of the mounting screws. The screws are self tapping so they just have to be "close enough."

Grommet is installed!

Through the other side. You can see the fuse holder that powers the system on the bottom.

Time to tackle the brake switch. Remove the plug and find a single pair prong brake switch, cruise control needs a second set of normally closed contacts to open up when the pedal is pressed.

The brake switch on the left and the vacuum switch on the right. New brake switch can be bought at the parts store for $5, vacuum switch is a bit harder to come by.

Oops. There's a clip for the brake switch that is needed in the other slot for the vacuum switch. And it's missing. Fortunately I still have the old brake pedal assembly, but I have to go out into the shed to hunt it down and get the clip...

Well, that was a good hour or so. Need to hunt down the clip, drill the servo holes in the inner fender, and then run the speedometer cables. Pretty straightforward.

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Last updated August 31st, 2015