Transmission update; borrowing Allen's pic

I hooked one switch to manifold vacuum and it now operates as it should(misspoke original post; was only getting 3 shift points & no tc lock). Thanks guys!

This poses the question: What is the other switch for? Its identical to the tcc switch(as seen in Allen's pic), 2-wire connector and 1 vacuum source. It's on the firewall above the passenter-side valve cover. Was it part of the now-missing emissions system? Or something else?

Geez, I'm getting as finicky as Allen. Oh well, its these little things that drive me crazy.

Appreciate y'all takin' the time,
Anthony

Now take 'er out and check your gas milage; you are going to be pleasantly surprised. :>)

That was back in the days when GM was scramblin' to smooth out that application of the converter clutch because owners were complaining that the darned transmission "shifted too often", so you'll see lots and lots of different configurations.

All the while, they had to met federal emmsion guidlines too.

If memory serves me, on your '86, they used two switches wired back to back. One was a normally open switch and the other was a normally closed switch to provide a balancing act to the solenoid because that transmission used as many as three pressure switches inside the transmission as well, which allowed the converter to come on 'just at certain times' in 2nd, 3rd and 4th gears depending on the operators' acceleration, deceleration, or cruise demands.

Also, along about this same time, they were playing with a solenoid control for the EGR valve instead of just using a simple ported vacuum source, as they went to the injection in '87.

I used to have all those circuits memorized, but it has just been too many years under the bridge.

Allan