I have a 1997 Chevy Suburban and I'm pretty sure that the fuel pressure regulator valve is going/gone. Or maybe it's just the elevation.
We recently had the water pump and the front intake manifold gasket replaced. Before that we didn't notice any trouble starting, but since then (just over a month ago) we've been having intermittent trouble starting it. Typically it starts a little rough in cold weather.
We travelled from Arkansas to Utah, so there's a huge elevation (and a fair amount of temperature) change. In Arkansas we attributed the trouble starting to the battery (it ran down a few times because children+dome lights have a tendency to do that), but since then and especially in Utah it would take quite a while to start. Sometimes several seconds of cranking. Occasionally at low RPMs (pulling out of the driveway once, a few times in a parking lot) the engine just dies. When we were pulling out of the driveway we were nose down at a slight incline (maybe 3-5%). It actually wouldn't start after several seconds of cranking. Finally we pushed it back into the driveway (10-30s), and then after a few seconds I tried again and it started.
At low RPMs it's really rough, sounds like it's going to choke and die. But revving the engine a bunch will kind of smooth things out. While driving at speed there are no problems.
The thing that leads me to think that it could be something else is that the fuel gage is wobbly. Fairly often it will just start waving wildly back & forth, which I've read could be a problem with the fuel pump.
Does this sound like it's the fuel pressure regulator that's at fault here? (unfortunately the thing is inside the engine, so it's not exactly easy to test).