In my case I was lucky, I have a bad vacuum line coming off my cruise control mod. It was a simple fix to cure both problems, thanks to the above conbributors, they are miles above my level. I think any of them would be of more help than I could ever be. They must know what they are talking about as it took me 30 seconds to diagnose the problem and maybe 30 minutes to fix it. I never even got into check valves.
Dan

 

ok my cruise has never "poped out" but i do have the "wild vents" problem and my front axle will disengage do u think the line thats the culprit is the same