Cruise control problem
Thread Starter
Racer
Joined: Jan 2004
Posts: 261
Likes: 0
From: Belgium WI
Cruise control problem
I have been trying to fix a cruise control problem on my 84. I have the vacuum lines fixed. My old servo had a broke off barb so the one of the vacuum lines was not connected on the bottom.
Took it out for a test drive..still doesn't work. If I push the switch to resume it goes to 55 mph and holds. Nothing else seems to work. I can not get it set by pushing the button on the end of the turn signal lever. Is it a bad switch maybe?
Took it out for a test drive..still doesn't work. If I push the switch to resume it goes to 55 mph and holds. Nothing else seems to work. I can not get it set by pushing the button on the end of the turn signal lever. Is it a bad switch maybe?
Melting Slicks
Joined: Jul 2003
Posts: 2,384
Likes: 124
From: Reno/Sparks Nevada
When the car is turned off the system should not have your old resume speed memorized. Try sliding the CC switch to off, start the car, drive it to any speed above 30 mph and then slide the switch from off to on then to resume momemtarily or a little longer. If the cruise speed sets then I would think the servo and electronics are working, maybe. It could be in the set function of the switch. My switch stalk broke one day, I bought a new one at the dealer and it was defective, a bad set function. Or...it could be as simple as the vacummn line at the brake pedal, or it could be the servo. There are a host of tests that can be performed with the service manual and meter. Start with my first suggestion. Check the brake pedal for a loose or disconnected vacuumn lines and check around the manifold or servo.
Thread Starter
Racer
Joined: Jan 2004
Posts: 261
Likes: 0
From: Belgium WI
I will check the vacuum line at brake pedal. All other vacuum lines are intact with no leaks. Didn't check this one though. Yeah, it seems like the cruise "remembered" that setting somehow. I will also try turning it on or off and starting car. Then try to set.
If it turns out to be the switch stalk how much is it and how hard to replace?
If it turns out to be the switch stalk how much is it and how hard to replace?
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
You can test the vacuum setup by disconnecting the cruise from the throttle plates, start the engine and connect a vacuum source to the cruise inlet.
If it pulls the cruise cable and holds position, hit the brake pedal to assure it releases.
If it passes these tests the problem could be in the switches or the dash cluster. The signal from the switches goes to the dash. The dash cluster has an output to control vacuum and detect position feedback.
If it pulls the cruise cable and holds position, hit the brake pedal to assure it releases.
If it passes these tests the problem could be in the switches or the dash cluster. The signal from the switches goes to the dash. The dash cluster has an output to control vacuum and detect position feedback.
