Reatta Mystery Cruise

[2seater]

Thanks Ronnie, I thought I was imagining things. I looked through the cruise schematics, hose routing and the diagram above. The FSM isn't very clear as to what is the "brake switch". It does look like two separate components. I see there are specific instructions as to when the various components are to activate based on pedal travel and it even mentions they "self set" by pulling back on the pedal to the stop, much like the TV cable for the transaxle? No intention to muddy the water but I have watched this thread to see if I could glean any insight into why mine doesn't do very well at high speed, like 80+. I make some assumption that perhaps my turbocharging reduces engine vacuum enough for it to lack the power to pull the cable :)

[Ronnie]

I think there is also a check valve in the vacuum line that has to be installed and working correctly for the cruise to perform properly. It's something else that should be checked.

[2seater]

I know my vacuum check/tee assembly is good but I found this interesting video of repairing the servo. The interesting part is the crumbling filter material, which is very similar to the vacuum valves in the HVAC programmer solenoids. I also found the homemade turbo system interesting as well as the comment about the turbo affect on the dump system?

 

https://www.bing.com/videos/search?q=replace+vacuum+cruise+control+with+servo+motor&view=detail&mid=44E00A710AC14A76D95C44E00A710AC14A76D95C&FORM=VIRE

[DAVES89]

That;s a great video. In the past I have always just gone out to Gibson's and grabbed another one. Maybe I'll try repairing one next time.

[jglawnyc]

Just to bring things round to the point or place of beginning.....As I prepared to go to the auto parts store to get a new brake switch and while my Reatta was peacefully at rest, I wrenched myself under into the footwell and grabbed the brake pedal post and showed it who's boss (gave it a light shake back and forth and side to side).  Since then the cruise control has worked every time!  I will replace the brake switch if the problem reoccurs.  Again thanks to all, see you in the next forum topic.  Its very satisfying to resolve problems myself (with the help of all of you out there), and a great bonding experience with our classic Buicks.