Anybody Know What This Is?

[emunstar]

I found this little guy hanging out and it looks like it at one time had a vacuum line on it. I cant find a severed vacuum line anywhere. Can anyone identify what it is or what it does? It is located on the firewall closer to the passenger side and has a 2 conductor electrical connector on the backside of it. I have an 86 K5 with the 305 and 700r4. Thanks for any assistance!

 

[dyeager535]

My guess is the 700R4 TCC vacuum switch. Unless someone comes on before and says yay or nay, should be able to check the wire colors at the trans TCC plug and find out. Also can run a continuity test, which is a better idea honestly, but tough to do with that distance.

 

[emunstar]

My guess is the 700R4 TCC vacuum switch. Unless someone comes on before and says yay or nay, should be able to check the wire colors at the trans TCC plug and find out. Also can run a continuity test, which is a better idea honestly, but tough to do with that distance.

Could a missing vacuum line to the switch cause a wide open throttle problem i.e. pedal to the metal and its like my foot is no longer on the gas. That is a recent issue that just popped up.

 

[dyeager535]

Better idea: check the emissions sticker on the core support. Will probably tell you what the valve is.

Probably not your issue, but figure out what it is, fix it, and see.

 

[emunstar]

Better idea: check the emissions sticker on the core support. Will probably tell you what the valve is.

Probably not your issue, but figure out what it is, fix it, and see.

I'll search for a picture of one online, mine is no longer readable.

 

[K85 Octane]

I had a computer controlled carb/dizzy/ and trans lock up. So I didn't have the valve. If your system doesn't really work, or you don't want to deal with it, look into the BTO 700r4 lockup kit. It replaces all that with a super easy electrical set up.

 

[Slade001]

Rotated

 

[onetonbb74]

I believe it is a vacuum switch that controls the electronic spark control and egr. If not follow the wire and see if it goes to the tranny, if so it's the lockup switch for the 700r4.

 

[Kain]

lock up switch for 700r4

 

[emunstar]

Thanks guys, I will get into it more in depth over my long weekend. I appreciate all of your replies

 

[pauly383]

the lock up switch is by the brake booster . This one is the tip in switch . Commonly removed when you run a regular hei and no spark computer

 

[emunstar]

the lock up switch is by the brake booster . This one is the tip in switch . Commonly removed when you run a regular hei and no spark computer

Tip in switch???? I think I will stop messing with it all and just wait for my buddy to clear out his current project. Once he is done we can get on with stuffing a 5.3L into Big Rusty.

 

[MAXMAN]

It's a converter clutch vacuum switch, part #14032087.