I think I'm going to start by replacing the transducer first and go from there.
http://www.corvetteactioncenter.com...erformance/140050-cruise-control-problem.html
I Googled my original post from 2013. Here you go. "here is how I fixed the speed control on my `82 last weekend, which will help you if you're a relative novice as me. Its almost always the transducer per my technician. The servo that is next to it and pulls the throttle cable, as told by the transducer when it is working, is supposedly fairly reliable. I bought my transducer at eBay for under $100 (reman'd) with an $11 refundable core. I would have paid more now, knowing how nice it is to have cruise control back, but its entirely your call if its worth it for everything to work in your Vette as a lot of good GM engineers worked hard to perfect, and was originally paid for by our predecessors...before they had kids and had to temporarily put aside their dream car. I thought so, but my regular shop quoted $350 for the job, so I saved big doing it myself as a very amateur hobbyist and the guidance instructions that came with it were straightforward. One online article said the C3 speedo design is a "primitive" design vs. today's, but it is a minor engineering marvel, and cool looking apparatus, inside and out if you have any appreciation for that sort of thing.
So, cutting to the chase, getting it out is a bona-fide bear. Maybe, give up now if you have extra-huge hands or extra-small patience. Reinstalling it is not quite as challenging because you've already moved the hoses/cables out of your way with tie-cables or tape, awaiting re-plugging in, and remember how to position your wrench and socket. And, because you know you're on a roll, clean new parts, etc. Do it in the natural daylight of your driveway - way too many shadows even with a bright shop light (I started but gave up the night before in my garage).
OK, first, remove the washer bottle top tube which is designed to separate from the washer bottle with one bolt then by careful twisting it off. Spray the joint with penetrating oil or silicone to minimize the separation effort(AutoZone sells a washer bottle repair kit if you get overzealous). Then, be sure to put a strip of electrical tape cushion on the sharp fender nut where that bolt attached to protect your hands in those tight quarters- or, put it off and have a few small bandaids handy like I did. Then, remove the hoses on the transducer, then the speedo cables - label their location with masking tape/marker - you'll be very glad you did. While you are at it, it is
important to remove the speedo cables (I tugged them out with needle nose pliers) and heavily lube them with lithium or other heavier grease. Don't worry - they feed back in easily while twisting. Put a gob of lubricant in your palm and feed it back in while lubing and twisting the cable. Then, unbolt the two attaching nuts and bolts - the toughest experience of my own C3 hobby experience to date. You'll certainly gain practice getting a wrench on the nut and a socket on the bolt due to interference and cramped spaces - but, use a longer socket extension and most importantly, a flexible joint (bought at Lowes, along with 2 new nuts and bolts) at the socket (put between the socket and the socket extension rod), coming in at as steep of an angle that you can, and be patient. Wear your glasses if you need them to save time. At first, when you finally get a bite on the bolt/socket, you'll sometimes measure turns in single clicks when you find that perfect angle.. and, that you'll have to re-find a few times. After you are victorious there, the rest is more or less down hill. Next, unbolt the `Resume'
solenoid bracket, if applicable (`81-`82)' while its still down in the fender nest. Its too large, or I didn't figure out the right Rubick's Cube angle despite trying - again, I'm new to this stuff. I would recommend clear coating the nice new transducer and silver- painting the old `resume' solenoid before you install it to give it a new, longer lasting OEM look if that's a goal. As a word of encouragement, it was a bit easier to reinstall the transducer than taking it out thanks to the (2) new acorn nuts and bolts that Lowes had in their slide-out `stainless steel fasteners' tray in the nuts & bolts isle, and hoses/cables being pulled back cleanly out of the way - at least a 3-4 minute task in itself.
The thrill of the cruise working about 2 hours and 3 band-aids later on a smooth-road test drive was a highlight of my entire day. My wife accused me of "beaming" when I came back from my test drive where the speedo worked, exactly as stated in the `82 Vette owner's manual. Good luck, be patient, and maybe spend a touch of that significant $ you saved by taking your co-pilot/wife out to celebrate... sitting on an outdoor dining deck, - looking out at your beauty parked in the vicinity of your hand picked open table - watching the next generation of C3 admirers and hobbyists staring and sometimes pointing at it as they walk by. Good luck and would be interested in knowing how it goes with yours! Dave"
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http://forums.corvetteforum.com/c3-t...ransducer.html
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