Starting problems

I have a 98 Plymouth grand voyager. Last year I had my starter replaced. A few months back, I started having problems again which usually happen in the morning. When I start the van, it starts up but then shuts off, as if the connection is not holding. This will happen several times and then won't start at all. If you leave it alone for a few days, it starts working again. I replaced the battery and had a full tune-up done. Was working fine for four weeks and it did it to me again this morning. Anyone have a clue what it could be?

From a Haynes manual you have 4 possible causes. 1. loose or faulty electrical connections at the distributor, coil, or alternator. 2. insuffient fuel reaching the injectors. 3. vacuum leak at the gasket between the intake plenum/fuel injection throttle body. 4. malfunctioning engine control system. Sorry but that's the best I can do for you. I haven't had that problem.