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Where To begin Door Lock Vacume Question

732 Views 3 Replies 4 Participants Last post by  ElRojo
All locks on the car have always worked nicely but awhile ago I noticed they started to become sluggish and then for awhile they'd all work (sluggishly) with the exception of the back passengers door which I would I have to walk around the car and lock manually. Is this perhaps a tip off or could it serve as a reference for a starting point for repair? None of the power locks work now and well you know not too good for dating!

Any help, tips, ideas or suggestions appreciated.

1989 300 SE
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It's not the valves you want to check, it's the vacuum pods. The vacuum actuators inside the door that react from the vacuum pump in the trunk spare well.

You might have to pull some interior carpeting first. All of the door lock vacuum lines are yellow.

The vacuum pods have a thin rubber diaphragm inside, and over the years they dry out, get britte, and crack. Once they crack, they cannot hold vacuum, and therefore cannot retract or extend.
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