I am going to delve into the world of the :ford: Thunderbird tomorrow. I am purchasing a '87 Thunderbird (base model). The seller informs me that the cruise control does not work. He related the following: "What it does is when you set the cruise it just speeds up and never tops off, until you either shut it off or tap the brake." So, with this bit of knowledge, can anyone tell me where I should start to look for the problem once I get my hands on the car.
Thanks
I have no clue, but I'll welcome you aboard.
You'll get an answer shortly
check the connections at the amplifier by your left foot. It may not be getting a signal from the VSS making it think it never reaches the proper speed.
oh yeah.... welcome to the board! lol
Also, the off button works (meaning electrical is probably ok) and the vacuum release valve at the pedal works. Perhaps the servo is bad...?
Thanks for the quick responses and welcome. I will tackle it this weekend. I am glad I found this forum.
Sounds like the Set/Accelerate switch is stuck.
I drove it home tonight after buying it and gave it a test run. When you hit the set/accelerate button all it does is accelerate. Is this a button issue or something deeper? Thoughts?
I'd tend to think if the button doesn't appear stuck down (does it?), it probably isn't, just because I've studied the construction of the actual button mechanism. Unless the plastic cover is physically pushing it down, it would pop up and lose contact. You could always borrow a puller from autozone and pull the wheel (5 min) and remove the buttons to test the continuity...
I had a similar problem a couple years ago only mine wouldn't turn off with the pedal OR the button. Even after killing the ignition (once the car reached 120+ overpowering my brakes) it still held and revved the engine to max. That was a bit dangerous. LOL My problem was the cable sleeve seperate from the servo housing and the cable just got stuck. But checking all the mechanical connections couldn't hurt, I guess
Wow, that had to be a crazy ride. I will check all the cable/cable connections from the servo housing. It may be the servo, I don't know. I hate to drop money on one and still not have the problem fixed.
If the set/accelerate was stuck I think it would start to accelerate as soon as you turned cruise on. You wouldn't have to push the set/accel button. Sounds like a VSS problem.
Does the speedometer work ok?
The speedometer works fine. What is VSS? Is that a speed sensor? Where is that located?
Vehicle Speed Sensor. If it's a C5, it'll be on the driver's side close to the tail shaft of the tranny.
The wiring comes through the 'hump' below the console, and there's a connector right behind the ash-tray/radio/junk collector box. It goes up to the speedo, then splits off and heads for the ECM and cruise control. The VSS in these old 'Birds is strictly a magnetic one, and has no excitation like newer VSS pickups. The conditioning of the signal is done at the other end(s). If your speedo is working, chances are it's a broken wire (between the speedo and CC), corroded connector at the Cruise Control amplifier, or possibly a dead input on the amplifier.
Thanks for the advice. I will check these areas out. All new territory for me, but hell, you got to learn somehow. I will post results, good or bad, as I go along.
you dont have to pull the steering wheel to remove the buttons and harness.
Not to hijack, but Old Paint, your comment about magnetic and exciter type VSS units: could this be why my 95 Mustang speedo isn't working even though I have double checked all the connections (12v, ground and VSS signal). thanks...
Well, I have checked connections under the dash and the wiring connections to the transmission with no obvious breaks or corroded wiring. I have yet to tear into where the servo is located.
Had an interesting twist during a test drive. I tried to set the speed using the cruise control and had the same result of continued acceleration until I hit the brakes. It was after this point when I stopped, made a u turn to head back home when the variant of what happened to booksix occurred. I was accelerating to get to highway speed, when after approx 35 mph the vehicle decided to start accelerating on its own. This continued until I hit the brakes. I did not use the cruise control during this incident. I am assuming the cruise control was still on (is there a dash indicator light showing that the cruise is on??)
So, I will keep the cruise off for now during daily driving until I figure this out. Not sure where to go from here, but I will check the servo this next weekend.
repace the amplifier by swapping it out with most any ford of like model / year and see if that changes things.
the servo is a different story. there isnt too much about the cruise i have not messed with.
swap the amp first.
let us know what happened.
no, there is no light to tell you the cruise is on or off.
if you need more info on the cruise, click on my diy link below or just search for my user name and all threads started by me.
Is the amplifier the little black box (under the dash) with the two connectors attached?
Disregard, I found a picture of it on RockAuto. Is this located right above the fuse panel?
Yeah, that sounds like an amp freak out. That pic it poor. It's a black box about 4" x 5" bolted to the firewall - not really above the fuse panel - using the bottom, drivers-side brake booster stud (studs come from the booster, through the firewall and pedal assembly and held tight with a nut on the pedal side of things).
Okay, I am picking up an amp this afternoon, so hopefully tonight I will have some positive results to report.
Picked up a new cruise control module (amplifier) today, installed it, took it for a test drive and everything worked as it should. Pretty excited as I have a 100 mile round trip daily commute, so it should come in handy.
I did compare the old module with the new one before install. Inside the old one the board (green card) was loose and rattled when I shook it from side to side. The new module did not do this and had a very tight fit with the connectors.
The amplifier was probably the original 1987 part, which would stand to reason as I pulled the original spark plug wires (they had 1987 printed on the wires), distributor cap, and one head lamp bulb (it had Apr 1987 printed on the base, it still worked by the way).
I would like to thank all that replied, as I know it takes time to sit down and respond to a question. But for those of us who do not have the knowledge or experience we definitely appreciate the guidance given by those that do.
on mine it doesn't work at all, not even close to knowing where to start?? anyone know?? sorry to use this one but figured why make a new one and crowd it up!
do a search on cruise control,,,
or
search all threads by jcassity,,,,,,,,,,,,,,,,
you will find a solved thread of an inop cruise.
the clip that holds the cable to the servo broke meaning my cruise was totally inop as well.
start a new thread,,,, this one is dead.
spoon fed the easy way:flip:
http://www.foxtbirdcougarforums.com/showthread.php?t=17452
Glad to hear it worked out! I LOVE CRUISE! Can't wait to have it working again after my debacle! LOL, hardest part will be getting the 04 expedition buttons working with the fox cruise (if I even can). anyway, no sweat, we are all glad to help!
and 84 cougarV8, definitely search and start with the basics! After that, start a thread with all your findings and we'll (we'll being me and all the people who actually know some stuff) be glad to help you out!
lol alright thanks guys! oh and gals if any! :D