Thermostat housing 2 ports what are they?

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Ricko1966

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I broke the hose nipple off one of those while changing the thermostat on my 79 Vette.
It looked just like yours. The one I bought looks a little different, but works the same.

If that's the one for egr it works exactly opposite. You don't want vacuum to egr cold but you do when the engine is hot. You don't want vacuum to efe hot You do want vacuum to efe cold. Try to blow through your switch cold,and hot to tell the difference. I just looked,that one opens at 104 degrees,wrong for what the OP wants, it's fine for egr.
 
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WFO

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If that's the one for egr it works exactly opposite. You don't want vacuum to egr cold but you do when the engine is hot. You don't want vacuum to efe hot You do want vacuum to efe cold. Try to blow through your switch cold,and hot to tell the difference. I just looked,that on opens at 104 degrees,wrong for what the OP wants, it's fine for egr.
Yeah, mine is for EGR. I thought his was the same.
 

Ricko1966

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Yeah, mine is for EGR. I thought his was the same.
I'm just glad it was caught before he had time to order one. That would have been a bixtch to have the heat riser closed all the time EXCEPT for warm up.
 

Lorenblazerk5

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Thanks again for all the trouble shooting tips!
I've done all the suggestions and each item seems to be working as designed.
the Temp sensor (pic below) on right has only 1 electrical probe, which is wired to the mixture controller solenoid on the carb.
Appreciate all the help identifying these crazy smog items on the CA k5.
You must be registered for see images attach
 
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