300D won't shut off!

My 1987 300D turbodiesel won't shut off all of a sudden. It keeps running after I turn the key off, although it runs rough, like it's trying to shut off, but keeps dieseling. The windows and door locks all work OK, so I
don't think I have a vacuum leak. What could be the problem? I'm gonna get real sick of opening the hood and hitting the kill switch!
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The last time I had this happen, the vacuum link to the shut off unit was loose. Plugged that hose back in proper, and the car shuts off perfectly. I'd check that vacuum link first, then start trying to find your culprit if it's not that simple.
Sure scared the begeebus out of me!
Mike

get
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Would that vacuum hose be right on top? Why would my windows and door locks still work then? And if it's a new shut off valve, is that right on top, too and easy to get to?

running
shut
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David,
I had no problems with my windows or locks when I had my shut off valve vacuum line loose... but I'm not positive I tried them. I'm pretty sure the line is on the top of the shutoff unit... it's the only vacuum line running to that whole pod by the manual shutoff lever. I just shoved it in nice and tight and it started working. However, my windows and locks may have been amiss but I never noticed -- not sure. I'd check the connection, maybe throw on a new elbow fitting just to be sure... $1 or less in parts and 10 seconds in labor is worth it!
I'll disconnect my line like it was this afternoon and see if my windows and locks still work, if you haven't figured things out by then.
Mike

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gonna
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You probably need a new shut-off valve. They're inexpensive and readily available.
Ron http://germanstar.net
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I had both the vacuumpump and the shut-off valve replaced; now everything works fine. Total cost in a non mercedes workshop 350 euro
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