97 Bravada Fuel System Questions

Our 97 Bravada has been running very erratically over the last several months, we've had it scanned quite a few times and a variety of things seem to come up at different times. At this point all 3 oxygen sensors, the MAF, the plugs and wires, rotor and various small filters and or sensors have all been replaced. I've heard from a couple of people that it is probably the fuel pressure regulator; however, in searching online and looking in service manual we have we cannot seem to find out where that part is located on the car. I've seen pictures/diagrams of the fuel system at several sites but there seems to be a couple of different kinds. Any help would be greatly appreciated. Feel free to post here or email me. :)

I had a similar problem with my '99. Trouble codes indicated intermitant miss on various cylinders, depending on the day and phase of the moon. Discussing possible remedies with my neighborhood mechanic, he observrved that the clamps on the duct between the air filterbox and TB weren't as tight as they might be. A few turns with a nut driver and my problem disappeared. We get lucky once in awhile.
I think you have an air leak someplace down stream of the mass air flow sensor which gives an overly lean A/F ratio.

That's one for the toolbox, thanks Lou.