1980 Cruise Control Experts - HELP!
Racer
Joined: Mar 2003
Posts: 282
Likes: 0
From: London
Re: 1980 Cruise Control Experts - HELP! (azswede1960)
mines a 79, so it might be a little different... but there is a vacuum hose that goes to the transducer. The other two hoses which come from the tranducer, join into one then connect to the servo which operates the throttle.
[Modified by Skeets, 12:44 AM 8/12/2003]
[Modified by Skeets, 12:44 AM 8/12/2003]
Pro
Joined: May 2003
Posts: 601
Likes: 0
From: Nottingham
Re: 1980 Cruise Control Experts - HELP! (azswede1960)
azswede1960,
I've put some stuff together on the cruise control sustem - hopefully you might find it helpful... have a look at
http://www.nottingham.ac.uk/~eaztl1/...leshooting.htm
Best of luck :cheers:
I've put some stuff together on the cruise control sustem - hopefully you might find it helpful... have a look at
http://www.nottingham.ac.uk/~eaztl1/...leshooting.htm
Best of luck :cheers:
Racer
Joined: Mar 2003
Posts: 282
Likes: 0
From: London
Re: 1980 Cruise Control Experts - HELP! (azswede1960)
yep i do...... but just had a look at Theo's fab write-up and there's a good picture in there of what it looks like.
Sounds as if you've got a couple of loose pipes?!
Sounds as if you've got a couple of loose pipes?!
Thread Starter
Instructor
Joined: Jun 2003
Posts: 135
Likes: 1
From: St. Pete Beach FL
Re: 1980 Cruise Control Experts - HELP! (theoUK)
Looks like some really good stuff - will be using it all this weekend. Thanks a bunch. I seem to only remember seeing a single vaccum hose.....maybe a quick fix for once ?????
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Instructor
Joined: Jun 2003
Posts: 135
Likes: 1
From: St. Pete Beach FL
Re: 1980 Cruise Control Experts - HELP! (theoUK)
One question: Looking at the picture of the transducer....Line E comes in from the brake pedal, and SPLITS into 3 lines (A, C & D) ? or am I looking at that wrong ????
Bubba has been under my hood for sure.....
Bubba has been under my hood for sure.....
Pro
Joined: May 2003
Posts: 601
Likes: 0
From: Nottingham
Re: 1980 Cruise Control Experts - HELP! (azswede1960)
Yup! You got it...
Obviously I cant vouch for individual systems, but they should be practically identical I would have thought, or at least identical in function.
A is where the "suck" comes from, but only when the system is set.
If you then block E and C from your mind, then the suction in A goes off up D to pull the servo.
Then E and C provide vents to let in atmospheric air:
In the case of C, it's a metered amount, controlled by the transducer.
In the case of E, its a big whack - this pipe is the one that opens when you hit the brake.
So think more of A and D being the highway, C's a farm track, and E is a dead end road until you hit the brakes!
Jeez, Where did that come from!?
:cheers:
Obviously I cant vouch for individual systems, but they should be practically identical I would have thought, or at least identical in function.
A is where the "suck" comes from, but only when the system is set.
If you then block E and C from your mind, then the suction in A goes off up D to pull the servo.
Then E and C provide vents to let in atmospheric air:
In the case of C, it's a metered amount, controlled by the transducer.
In the case of E, its a big whack - this pipe is the one that opens when you hit the brake.
So think more of A and D being the highway, C's a farm track, and E is a dead end road until you hit the brakes!
Jeez, Where did that come from!?
:cheers:
Thread Starter
Instructor
Joined: Jun 2003
Posts: 135
Likes: 1
From: St. Pete Beach FL
Re: 1980 Cruise Control Experts - HELP! (theoUK)
Took a trip down to garage at lunch to look at transducer a little closer....looks like all the hoses are there and connected up, including the "E", where is the other end of that one? Is that at the break pedal, some switch like the break light switch up under there ?
I will be doing the comprehensive vaccum/electrical troubleshooting when i get my car bac at the end of the week, but want to make sure I know where I should be looking.....by the way, I thought I had a vaccum leak under dash......maybe this is the culprit ????/
I will be doing the comprehensive vaccum/electrical troubleshooting when i get my car bac at the end of the week, but want to make sure I know where I should be looking.....by the way, I thought I had a vaccum leak under dash......maybe this is the culprit ????/
Pro
Joined: May 2003
Posts: 601
Likes: 0
From: Nottingham
Re: 1980 Cruise Control Experts - HELP! (azswede1960)
Yeah E is the line from the Brake pedal. There's a vacuum valve on the pedal that opens when you hit the brake, and lets air in to the system, via E, to let the servo relax.
If you think you had a leak under the dash, (i suppose you could hear a hiss?), then maybe that brake pedal valve is staying open or not sealing. That would stop everything from working.
Next time you have a couple hours free, I'd just methodically work thru the list of stuff I've put up, so you can work out bit by bit what's
not wrong with it - if you have a vac pump its a whole lot easier. You'll get it going - I bet it's just something stoopid :)
If you think you had a leak under the dash, (i suppose you could hear a hiss?), then maybe that brake pedal valve is staying open or not sealing. That would stop everything from working.
Next time you have a couple hours free, I'd just methodically work thru the list of stuff I've put up, so you can work out bit by bit what's
not wrong with it - if you have a vac pump its a whole lot easier. You'll get it going - I bet it's just something stoopid :)
Thread Starter
Instructor
Joined: Jun 2003
Posts: 135
Likes: 1
From: St. Pete Beach FL
Re: 1980 Cruise Control Experts - HELP! (theoUK)
Is the vaccum valve on the pedal the same physical piece as the brake light switch or is it totally different piece ? I only have the brake light switch....and it doesn't look like it has any vaccum fitting on it, but it could have been swapped out by Bubba I suppose ..........
Pro
Joined: May 2003
Posts: 601
Likes: 0
From: Nottingham
Re: 1980 Cruise Control Experts - HELP! (azswede1960)
Ahhh, I'm not entirely sure!
This part of my system worked ok, so i didn't venture under the dash....
Can you tell anything from those images I put in of the workshop manual? They show the component location, although it's not crystal clear.
BUT, are you sure it's not just hidden up among the general tangle of stuff up above the steering column?
Most importantly, does pipe E hold a vacuum?
Have you tried to suck (need to extend it a bit, or get a helper!) on the pipe E, then push the brake? It should hold the suction until you push the pedal. Try that - sorry, I'm not sure what state of disassembly you've got it all at, so don't know what you can and can't see.....
This part of my system worked ok, so i didn't venture under the dash....
Can you tell anything from those images I put in of the workshop manual? They show the component location, although it's not crystal clear.
BUT, are you sure it's not just hidden up among the general tangle of stuff up above the steering column?
Most importantly, does pipe E hold a vacuum?
Have you tried to suck (need to extend it a bit, or get a helper!) on the pipe E, then push the brake? It should hold the suction until you push the pedal. Try that - sorry, I'm not sure what state of disassembly you've got it all at, so don't know what you can and can't see.....
Racer
Joined: Mar 2003
Posts: 282
Likes: 0
From: London
Re: 1980 Cruise Control Experts - HELP! (azswede1960)
re: the brake light & vacuum switches... no they are not part of one big switch (just had a look on my79) ... they are mounted one above the other infront of the brake pedal, though on a common bracket.
The bottom electrical switch has two plugs attached to it, one for brake lights & the other for C/C (electrical dissconnection).
Above that is the vaccum switch.... it just looks like a little piston thing stuck in the end of the vaccum pipe, nothing very complex.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 135
Likes: 1
From: St. Pete Beach FL
Re: 1980 Cruise Control Experts - HELP! (Skeets)
Thanks Skeets & TheoUK - I guess I will have to find it......think that is what I am missing......I have more than enough to get me going as soon as I get my ride out of the glass shop :)
Thanks again
Thanks again
Thread Starter
Instructor
Joined: Jun 2003
Posts: 135
Likes: 1
From: St. Pete Beach FL
Re: 1980 Cruise Control Experts - HELP! (theoUK)
Ok - checked out vaccum hoses, each and every one.....then on to electrical, blue wire checked out BUT green did not have any voltages. Went under dash and checked the connection from the steering column (1 small 3-wire ribbon cable) into cruise connector. Felt tight but gave it a little elbow power.
Checked it again and now have voltages! :party:
Took it around neighborhood to get it above 30mph and hit the CC button....it stayed.....kind of anyway, seems like it was bouncy, but could just be my imagination. Will take it out on the open road to test as soon as I get a temp registration.....but there has been definite progress at minimum :chevy
Checked it again and now have voltages! :party:
Took it around neighborhood to get it above 30mph and hit the CC button....it stayed.....kind of anyway, seems like it was bouncy, but could just be my imagination. Will take it out on the open road to test as soon as I get a temp registration.....but there has been definite progress at minimum :chevy
Pro
Joined: May 2003
Posts: 601
Likes: 0
From: Nottingham
Re: 1980 Cruise Control Experts - HELP! (azswede1960)
Woohoo!
Glad it's giving signs of life!
If "wiggling" that connector you were taking about gave you power, then it might be worth just opening it (the connector) up again and making certain its all clean and good - after all, it could just be dirty, and might cease to work again in the future - putting you on another wild goose chase trying to sort it out.
When you get the chance, engage it at a decent speed and see what you get!
:cheers:
[Modified by theoUK, 3:06 PM 8/16/2003]
Glad it's giving signs of life!
If "wiggling" that connector you were taking about gave you power, then it might be worth just opening it (the connector) up again and making certain its all clean and good - after all, it could just be dirty, and might cease to work again in the future - putting you on another wild goose chase trying to sort it out.
When you get the chance, engage it at a decent speed and see what you get!
:cheers:
[Modified by theoUK, 3:06 PM 8/16/2003]
Thread Starter
Instructor
Joined: Jun 2003
Posts: 135
Likes: 1
From: St. Pete Beach FL
Re: 1980 Cruise Control Experts - HELP! (theoUK)
Took it out for road test, and same thing is happening once I set the CC -
it surges then lets go... continously. Any suggestions or just get a new transducer ???
it surges then lets go... continously. Any suggestions or just get a new transducer ???