Thanks for checking in on this thread! I just bought an '88 GT and noticed that it has cruise control servo and cable system installed, but no cruise control switches anywhere, and the wiper/cruise stalk is chrome with no cruise functionality at all.

Here are some pictures of what I found:

First, I found a wire cut on each side of the main gauge cluster. It looks like there are two wires (red) that intercept two green wires, one on each side of the cluster. I don't know if this is related to the cruise control, but maybe.






Tapped into the ECM wiring I found this setup:



Lastly, there's this harness coming through the firewall connected to the cruise servo in the engine compartment:













This is what the text says on that cruise control unit:
"SPEED CONTROL
ELECTRO
SERVO
P/N 017300849 (hard to read, probably wrong)
US PATENT NO 658407 (hard to read, probably wrong)"


Any help? Any suggestions? Has anyone seen anything like this before? I really want the car to have cruise control, so I'm considering what it would take to get this working again, or to just try and swap in a working cruise system from a different car.

Your first 2 pictures look like the 'Temp Gauge Fix', and probably are not related to cruise control. If you can turn your key on, and the temp gauge does not peg to the right (and you get a temp light), these wires are the reason why. You can search for the instructions to see what has been done.

That makes sense, based on what you describe, that is what we're looking at here.

And the rest of the pictures are showing wires and components that are not factory.

------------------
Rod Schneider, Ball Ground, Ga.
"You can't have too many toys!"
1988 Fiero GT
1988 Porsche 928S4
1987 Corvette
2001 Chrysler 300M
Van's RV-6 airplane

Switch it over to an AR digital module, looks like most of the wiring is done for you. Go to gmtuners.com and get the pinout there.

quote Originally posted by hiwil88formula: Switch it over to an AR digital module, looks like most of the wiring is done for you. Go to gmtuners.com and get the pinout there.

Thanks. I saw the pinout diagram, but what is "AR" in reference to a digital cruise control?

Its the cruise control module everyone uses and has the pinout for. Very common in late 90's gm cars, prolly take about 10-15 minutes at a junkyard to find one. You will need the cable and the pigtail for it to make it work. Look for a module that has "AR" printed on top of it. I paid at most $20 for one here.

[This message has been edited by hiwil88formula (edited 04-03-2015).]

Good to know, thank you!