1997 Infiniti QX4 Hard Start

[edracer88]

I have a 1997 Infiniti QX4 (155k miles) that is very hard to start, and once started will not run under anytype load. The first indication of my problem was when the car died as if it ran out of gas. I changed the fuel filter which was pretty much plugged up. The vehicle ran fine for a day or two and then became very hard to start. Once stared I could drive it around town and it would die when I got on the throttle. Now I can barely get the vehicle started-What's Up?

I've tested the fuel pump psi per the FSM and found it to be slightly higher than the recommended spec (45 psi). The pressure gauge is somewhat erratic but only with a 2 pound swing. When the vehicle is shut off I notice the fuel psi drops to zero pretty fast. I'm not sure about the fuel pressure regulator-when I pull vacuum on the regulator the fuel pressure will drop as noted in the FSM, but the regulator is not holding the vacuum (might have a bad connection with my vac pump-this regulator is HARD to get to) When I do get the vehicle started, it will idle fine, when I start popping the throttle, the engine will start to sputter and die. The fuel pressure never really changes when I'm messing with the throttle. Could I also have a MAF problem? i've read several threads related to the MAF and fuel pumps. I'd like to figure out what is going on before I start throwing lots of dollars at replacement parts. Any help or advice would be greatly appreciated.