my 84 300SD will keep running even after the key is turned off, unless the heater/ac is on. i'm asumming that is must be a vaccume leak some where. but where? its been happening for a while now. i thought that changing the mono valve might fix it, but i'm still waiting for my valve, so i haven't changed it, and i was wondering of you guys thought that the mono valve might be part of this problem, or if it was somethign else.

You have a vacuum leak ...someone will chime in with a better more specific place to look than I can at this point. But its related to the the pods under the dash most likely. If you have a mightyvac you could check them one by one...I've never sat down and had to go through this so sorry I can't be more specific than this.

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Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
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Section 609 MVAC Certified
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