Identify this???? 1st gen F body????
 

I am attaching a picture of a gadget that is plugged into the wire harness on the engine by side of a 68 Firebird. It has a spring loaded plunger. The plunger appears to be a ceramic material. The housing is threaded like a giant brake light switch.

Any idea what this is?

TH400 kickdown is electric, is it possible that the car had a TH400 originally? Also had a fast idle solenoid for a/c cars, but those are usually one wire.

Odd - it wasn't a TH400 car. I do have some cryptic at best tear down photos that show an electric device (like a fast idle solenoid) on the carb - but it isn't this part. I do see a bracket on the old carb that has a round hole in it like this device could plug in there. However, the device isn't in the picture -nor any part of the harness. The part of the harness that feeds this mystery one feeds off the harness that goes to the starter, wiper motor - and over to the heater box. Was a non-AC car. The solenoid device I can see in the picture is plugged into the front of the carb (clearly not the part we are looking at here) and it is being fed off the part of the wire harness that comes in from the alternator.

did those cars have any type of ram air box or air cleaner with a door in it that this solenoid could open?

doesn't look like they did have anything that moved on the ram air cars. That solenoid is similar looking to some of the TH400 switches I've seen. That's still my vote............... :)

That? Oh yeah, that's one a them there doohicky thingamajiggs. Very common on old cars. Yup, that's what it is for sure!
I believe it was originally installed next to the dual quad chrome dipstick. :D

I pulled the part and cleaned it a bit - it says:

Littel fuse 4-8 on the back. So far no luck on a google for that.

The car is up and running - I have all the circuits that I believe the car needs under the current configuration. This is just baffling me.

Also, there is no extension on the wire harness that would indicate anything would have plugged into the transmission - as in some kind of wiring to go to a TH400.
:question:

Possibly something for cruise control? I have a cruise control stup on my 68 firebird. I'll have to see if I have that still plugged in. Ot at least those plugs.

I was thinking cruise control as well but I thought kickdown and cruise control was controlled by vaccum at that point in time.....

No other signs on the car that it had cruise.

Very confusing.

I need to put my meter on it (if it still works) to see when it opens/closes the circuit as far as being pushed in or stationary. It might even be variable.