Dodge Repair: Dodge Caravan 1993, dodge caravan, vacuum line

Question
Dodge Caravan 1993, 180K+ miles

Every so often the van just quits, quietly dies.  If we get out and remove a particular line/hose, a small one, only about a 1/4 of an inch around (I don't know which one, but it has something to do with the cruise control, because it won't work when the line is off), it will start again and run fine.  Whenever we remember, we put the line back on, and it will work well for some random length of time before pulling the stunt again.  This isn't urgent, it's been going on for several years.  My urgent question follows...  Any thoughts?

Too, the a/c won't run, and the engine cooling fan we've replaced, but it won't turn on so the van overheats regularly (TX, hot summers).  We've taken  it in for the a/c twice and no one can tell us why it doesn't work.  Does the a/c problem have to do with the cooling fan problem?  What have we missed?  Is this the relay that everyone is talking about?

Thank you so much!
Erin Speciale

Answer
It's most likely a relay for the fan. However, the line you are removing is a vacuum line, since I haven't heard of this before I really don't have a clue what it is. I'd just leave the vacuum off if you can deal without cruise control. If it doesn't seem to pose any other issues, it should be fine.