What is this?

[xenomarine]

So I've always wondered what this is. Apparently none of my friends know either. It has a vacuum line attached at one end to manifold vacuum, with brown and yellow wires coming out of the other side. Both enter the firewall right behind the transmission dipstick tube, and the brown wire looks to be a ground. It had been crimped (I think from the factory) to something that had been cut out at some point, as well as to a ground attached to the block.

 

[diesel4me]

Maybe a torque converter clutch switch,but it doesn't look like the one on my 81 G-10 van with a MV4/TH350 with a lock up converter--..could be some other funky thing ,I've seen aftermarket switches that cut out the A/C compressor when engine vacuum falls to a lower level so you gain a few more HP for hill climbing or passing..

 

[Stomis]

Lockup for the converter on non computer controlled carb?

 

[xenomarine]

Ah okay I thought I had already removed that but somehow this remained. I reran my lockup wiring to operate on one wire so it's already bypassed.

 

[runamok151]

vacuum relay for the flux capacitor.

 

[earnett]

That is for electronic spark control. The switch converts vacuum into a voltage signal so that the computer knows how much throttle your giving. If you have a lock up converter you will have a second one near the brake booster. There may also have been wiring for the egr coming from there to. Looking at your pics it not doing anything now but pluging the vacuum line. You can remove all of it without worry.