Vacuum Switch Identification

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rct859

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Hello! I’m currently Doing some work on my 86 k10 swb with the cab and bed off. After pulling the cab I found A switch zip tied to the transmission dipstick. 700r4. It appears to have two vacuum connections on it, but hasn’t been hooked up for a long time. Its wires connect into the harness that goes to my transmission plug. I thought it may be the converter lockup of some kind but that’s near my brake booster. Any thoughts on what this is for? I will take a better picture tomorrow.
 

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Ricko1966

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Are both vacuum switches in place on the firewall? There should be 2 . One for converter lock up,in for ignition tip in.
 

rct859

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Are both vacuum switches in place on the firewall? There should be 2 . One for converter lock up,in for ignition tip in.
Yes I have one near the brake booster and one near the Blower motor
 

Ricko1966

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Yes I have one near the brake booster and one near the Blower motor
K get us better pics tomorrow. In that Pic it looks like the egr bleed solenoid.
 

Jgonick

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I found A switch zip tied to the transmission dipstick. 700r4. It appears to have two vacuum connections on it, but hasn’t been hooked up for a long time. Its wires connect into the harness that goes to my transmission plug.
Are both vacuum switches in place on the firewall? There should be 2 . One for converter lock up,in for ignition tip in. In that Pic it looks like the egr bleed solenoid.
EGR
see attachment:
 

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rct859

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That seems to be it, the Wires running to it are yellow and Light blue. Thank you. I’ll cut it the rest of the way out.
 

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Ricko1966

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That seems to be it, the Wires running to it are yellow and Light blue. Thank you. I’ll cut it the rest of the way out.
Why?,I'll take it and the connector. If you don't want it.
 

rct859

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Why?,I'll take it and the connector. If you don't want it.
I don’t have an egr on the engine and won’t be adding one back, most likely why it was moved out of the way to begin with. I’ll let you know when i get to stripping some more wires out of the bay.
 

Ricko1966

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I don’t have an egr on the engine and won’t be adding one back, most likely why it was moved out of the way to begin with. I’ll let you know when i get to stripping some more wires out of the bay.
Thank-you
 

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