You dont need to buy a fuel pressure gauge most auto parts store will loan you one. Fuel pressure is the basis for any type of fuel system trouble shooting, sure there are all kinds of wife's tale's and home cooked options to follow and perform. I prefer to take a more stepped scientific approach by using real fancy tools like gauges and meters LOL
Disagree all you what I still want to know want the fuel pressure and possible the fuel flow rate when the OP's **** is hot.