I was trying to remove the glow plugs for an eventual compression test, and in the process noticed a crack/hole in the rubber bit holding the vaccuum line to the shutoff valve. Since I had the line off to replace it anyway, and was curious, I tried hooking the MityVac to the shutoff valve and applying vaccuum (with engine off). I noticed two things 1) It does not hold vaccuum ... it holds for a couple seconds than drops down and 2) the stop lever doesn't move at all. The car has been shutting off pretty normally as I can tell, so I'm assuming if I applied vaccuum with it running it would still shut down. Are my observations with the engine off an indication the valve may be in the process of failing, or are they normal? I've read a lot of posts saying vaccuum applied to that nipple should move the stop lever down, but I was thinking that might be in reference to the later IPs? Mine has the kind of lever attached to the external throttle linkage as opposed to side of the IP.
So, should I just plug it back in (with new rubber connector obviously) and not worry about it as long as it shuts down easily, or is it a problem waiting to happen? Anything that has to do with the shutout valve freaks me out a bit, because of all the runaway threads I've read.

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