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Vac Hose, Mystery Location Needed

Old 05-13-2019, 10:21 AM
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Default Vac Hose, Mystery Location Needed


I am trying to put my '90 back together, and I am not sure where a vac line goes.

See the attached picture for reference. I believe the location to plug this in should be near the distributor. I was working "blind" when I took it off and thought I heard a snap, then it came out. That is never good...

Now, I can't figure out where it goes.


-Tim in Mass

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Old 05-13-2019, 06:37 PM
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Since it looks like the other two vac lines are running properly my guess is that hard line goes to the HVAC control.

Plug that line, start her up and see if HVAC controls work properly.
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Old 05-13-2019, 10:15 PM
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Hard to tell from the picture and Im not sure what has changed from my 85. Is the other end connected to the back of the two ports on the plenum? With the check valve, my guess is it goes from that back port on the plenum to the hvac that routes past the left side of the distributor. Those plastic lines are know to break pretty easy when their this old. Mine runes down the left side of the distributor and drops down over to the left side of the car kinda by the washer fluid bottle if I remember right.
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