Diesel will not turn off
 

I have a 1992 300D 2.5 Turbo. Recently I noticed when I turned the key off the engine would run for second or two longer then normal. Now it will not shut down with the key. I notice when I open the hood and just touch the stop lever she quits. when I pull the vacumn line off the actuator the lever come right up (rotates 90 degrees). All this seem correct other the the lever is not quite getting all the way down to shut off the engine.

I have check most all the vaccumn connection and the are all good. I will check tonight to see if when i put a Mityvac on the actuator hose if that does it which would indicate the vaccumn is weak and still could be a connection.

I did notice when I pull the hose off that there was just a trace of oil on the tip. If this is the source of the problem how do I fix.

Thanks Squire