Author Topic: What to check on my 86 Sierra to fix my cruise control  (Read 4071 times)

Offline lbrowne

  • Newbie
  • Posts: 65
What to check on my 86 Sierra to fix my cruise control
« on: May 16, 2010, 07:41:50 pm »
Doesn't engage at all, I'd love for it to work since that's one option I like to have to keep my lead foot from droppin down.

I would imagine the system is not too complicated - any help you can throw my way would be appreciated.

Cheers,

lbrowne
1986 GMC Sierra Classic
My first truck! (completely stock...for now)

Offline Skunksmash

  • Senior Member
  • ****
  • Posts: 1398
Re: What to check on my 86 Sierra to fix my cruise control
« Reply #1 on: May 17, 2010, 06:02:24 pm »
Well I'm sure there are other people that can help a lot more than I can, but for me it was a combination of the actual button itself being broken, along with a vacuum leak. I would start by checking the cruise system for vacuum leaks.

Offline VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 19167
Re: What to check on my 86 Sierra to fix my cruise control
« Reply #2 on: May 17, 2010, 07:45:31 pm »
A little more detail on what you've checked so far? Is it connected?
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline lbrowne

  • Newbie
  • Posts: 65
Re: What to check on my 86 Sierra to fix my cruise control
« Reply #3 on: May 19, 2010, 12:29:05 pm »
Everything appears to be connected. The button on the switch has no excessive play, it appears to be functioning.

Where are the vacuum lines for this located? The vacuum lines that goes into the front of the carb appears to be loose, going to tighten that up.

I'm thinking that is what it is. Is there a fuse for this system?
1986 GMC Sierra Classic
My first truck! (completely stock...for now)

Offline induction

  • Newbie
  • Posts: 8
Re: What to check on my 86 Sierra to fix my cruise control
« Reply #4 on: May 24, 2010, 02:13:08 am »
I'm in the same situation, but I have a 1978 Sierra w/ factory cruise.  I'm hoping both are similar?  I can't seem to find a fuse that's specific to the cruise - is it labeled in a particular way?  The blower fan that's supposed to spin at all times (even with vent off) is no longer spinning - is this related to the cruise not working too?  Thanks!

Offline Skunksmash

  • Senior Member
  • ****
  • Posts: 1398
Re: What to check on my 86 Sierra to fix my cruise control
« Reply #5 on: May 27, 2010, 11:31:29 am »
My button had no excessive play either. There is something inside those switches that can go wrong, and the button still appears to function normally. That is what happened to mine, anyway. I fixed the vacuum leak myself but then ended up taking it to the shop when I couldn't find anything else and they had to put a brand new blinker bar on for me. Looks nice now, and the cruise works.