Another topic reminded me of this quirk:

My mercedes usually doesn't shut off when I have my doors closed. If I turn off the ignition, the engine will continue to run until I open the drivers door, and then it will slowly come to a stall.

If I open my door and count to five, the engine stops immediately when I shut off the ignition.

It doesn't bother me so much, rather I think it's an interesting quirk, but I can't help but be curious as to why it behaves like so.

Any ideas?

leak in door supply line.

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1985 300SD
1983 300D
2003 Volvo V70

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Mine did that in the early days of an IP shutoff valve failure.
Get out the mityvac, look for leaks, and check your lines for oil...

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