'79 Olds 403 Parts


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Jul 27, 2019
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I'm having a helluva time replacing two parts that attach to the intake manifold. Can anyone help? The first is called a temperature sensor, according to the diagram below. This is not to be confused with the temperature sending unit, which is installed toward the front of the manifold.

Vacuum Diagram.jpg

To complicate matters, the temperature sensors I'm seeing online have an electrical hookup. My original--if it is in fact the original and if it is actually a temperature sensor, looks like this:


Notice that it isn't an electrical hookup but a hose hookup. To this novice, this doesn't look like a temperature sensor at all but instead a simple 1-port manifold vacuum fitting. What do you think?

The second part I'm looking for is a 2-port manifold vacuum fitting, as circled in yellow in the diagram above. The manifold opening measures 1/2-20 but the fittings I'm finding online are all 3/8. I'm pretty sure the second port connects to the brake system. Here's the pic of the original:

front manifold vacuum fitting _3_.jpg

Thanks for taking the time to read this far and for any insights you can provide to point me in the right direction.
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