cruise issue

[Shimy87]

Its always something . Cruise started failing this weekend. It will set but then slowly slow down, I looked at hoses going to the diaphram thingy and the seem good. I'm sure this is a common problem, what should I check?
 
Thanks!!!

[Just a Six?]

Mine won't even set anymore? Haven't checked the fuse but I doubt that it's the problem?
I haven't really checked what may be the issue as I don't have the need for it very often.
I will keep watching this thread to see what you find out? 
 

[Jeff]

why would i wanna set cruise when the pedal is floored

[SuperSix]

Its always something . Cruise started failing this weekend. It will set but then slowly slow down, I looked at hoses going to the diaphram thingy and the seem good. I'm sure this is a common problem, what should I check?
 
Thanks!!!

I would think the most common failure is a vacuum issue - check ALL vacuum lines, hoses, check valves, etc.

[Shimy87]

I figured as much, was hopeful someone would point me to a common area of failure

[SuperSix]

Improper brake pedal switch/vacuum break adjustment is another failure, but it's not gradual.

[Shimy87]

Went for a cruise tonight and the vents wont switch from floor to dash. Considering just replacing all the vacuum lines. Can you get thoses little check valves at a parts store or must they be ordered online?

[Steve Wood]

Went for a cruise tonight and the vents wont switch from floor to dash. Considering just replacing all the vacuum lines. Can you get thoses little check valves at a parts store or must they be ordered online?

http://www.vortexbuicks-etc.com/acvacuumswitch.htm

http://www.vortexbuicks-etc.com/heater_cable.htm


try the Help section for the checkvalves at the parts store

[Shimy87]

Thanks Steve!! The issue I'm having is the door wont change position to change air flow from floor to vent, it will turn AC on and off. If this switch is bad would you hear the vacuum hissing in the cabin? I assume there is a hose leading into the switch? If thats the case maybe its broken/leaking in the engine bay causing the heater control and the cruise not to work.
 
I'll dig into it tonight.  High 90 degree temps and high humidity here, need to get this AC working

[SuperSix]

http://www.amazon.com/ACDelco-14047619-Cruise-Control-Vacuum/dp/B000C982H2

That's what I used - there's a list here, or on tb.com of the sizes and lengths..

[Steve Wood]

Thanks Steve!! The issue I'm having is the door wont change position to change air flow from floor to vent, it will turn AC on and off. If this switch is bad would you hear the vacuum hissing in the cabin? I assume there is a hose leading into the switch? If thats the case maybe its broken/leaking in the engine bay causing the heater control and the cruise not to work.
 
I'll dig into it tonight.  High 90 degree temps and high humidity here, need to get this AC working

If you look at the link I sent you, you will see multiple hoses.

The second link can also cause the problem...

[daveismissing]

The blend door lever was unavailable, IIRC correctly Kirban now has a repro.
After I had to do my fix:
http://dtekk.com/automotive/heater/heater.html

[SuperSix]

Sounds like an engine bay vac leak to me.

After replacing all the hoses on the 87T, testing etc - it started doing that vent thing too - turned out I had tugged the pink vac line from the bulkhead connector to the right of the glove box, under the dash.

I bought a new A/C Delco dash vac switch, (I ASSumed that was the problem) - so the new switch is going in the GN!

[Steve Wood]

given the symptoms it does sound like a split line or such...pull the hose off the back of the switch and see if it has vacuum on it...and how much if it does

[Shimy87]

Got it fixed. It was a cracked hose coming off the tee hidden inder the egr