12 Volt vacuum pump problem

actually looking a your diagram, i would remove the check valve that is shown between the pump and the pressure switch. because if it ever sticks or fails your pump will never shut off. as someone else has mentioned, we really need to know what kind of voltage and amps you are pulling, the more info. the better we can help.

If you were a bit closer to me i wouldnt mind stopping up and assisting, but looks like your outside of allentown witch is a few hrs away :(