dumbkidwitha94Z28

So I just bought a 94 Z28 and have put about 1,500 miles on it, its only done it 2 or 3 times but it will start making a weird noise and the oil pressure drops and car dies and wont start until you let it sit without running for about 2 minutes then starts up fine and acts like no problem, it sounds like my fuel pump could be going out or maybe its a sensor not really sure, I believe it does have an aftermarket mild cam in case that would have anything to do with it. and only does this when it sits idling. thank you.