My gauge's are not reading when I try to start my van.

What is your question?

Sometimes my gauge's work and don't work. When it does works, and it starts, it will stay on for a few minutes and die, then the gauge's don't work again. I wait and try the van the next night same thing. I have changed the fuel filter, cleaned the gas tank, changed the IAC sensor, I have has a couple of so-called Machanic look at it, but they have no answers.