92 S10 vacumm problems

I have a 92 S10 with the 4.3. I recently took the temp control module out to clean the connections on the wires. They get real hot when using the medium fan setting and melt it or glaze over the connections. I cleaned
those and the fan works again.
At the same time I pressure washed the under side and top of the motor to clean off the mess from when the radiator was leaking which has since been fixed,.
Now I do not have any heat or vent. They justmake a hissing sound and comes out the defrost. If I turn it to Bi-level for ac it works, but when I give it a lot of gas it roll sback to the defrost then when I let up it goes back to bi-level.
I've checked every single host under the hood and all are hooked up and no cracks. The hiss is from inside the dash.
Did Ipull ahose lose inside somewhere? I followed all that I can and cannot see that they are lose. If I turn it to vent or heat the motor idles down back to where it should be,
Any ideas?
Lannie
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The selector that controls your air location, IE floor mid vents or defrost is vacume controlled. I had a selector switch for one of these crack and a tiny piece broke off and it made the same hissing sound you described. It turned out on mine I had to get another selector switch from the junkyard. Where you pulled the temp control out I would say perhaps the same thing happened to you. Or you have a different vacume leak else where and the system doesn't have the oomph to move the gate to change the air flow, as desribed by giving and letting off the throttle. With the systme running, find the actual source of the hiss. It will help figure out what is wrong.
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Lew Pratt
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It is definitely hissing from behind the selector. The little snap piece that holds the part that spins broke a year ago. I found a plastic door clip for a ford that had the same size of shaft the broken clip had and made a new one. I wonder if that wore out and is loose. I think I will hit the junk yard.
Is there a module or something is causing my switch to melt the connector where the wires plug in? There is a module on the firewall next to the fan. Would that be causing it?
Lannie

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The melting of the wires on the connector sounds like there was too much current going thru the wires. I am not really sure how to diagnose this with out being there. Perhaps one of the other guys could help on that one.
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While we are at it, has anyone ever changed the o-rings in the remote oil filter where it connects to the block? How do you et to it???
Lannie

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fan.
It is likely that the connector terminals have lost their tension and are creating resistance, which in turn create heat. You may have to replace the terminals or find a replacement pigtail to correct the problem. H

to
help
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