1999 Ford E-150 4.2L

This E-150 has really been a great van, 171,000 miles with no problems until now. One day on the way to work the Engine started skipping a little then shut off completly. Replaced fuel filter, old one plugged up pretty bad with who knows what. first time filter has ever been changed. No longer have a problem with engine shutting off but it now takes two or three times to start the engine and it runs really rough for about 30 or 40 seconds then clears up and runs perfect most of the time. You can shut the engine off and it will start back up the first time with no problems. If the engine sets all day or over night then it will again take two or three times to get it started and will again run rough for 30 seconds or so. I added fuel injector cleaner (Seafoam) in the tank last week does not seem to have helped it. I'm thinking it is a fuel pump or regulater problem. Anyone ever have this problem? any suggestions? One other detail I need to mention. The engine light has been on for over a year now but I have had no problems with the way the engine runs until now. Code reader shows a MAF or VAF P0102.

Regards
John

Checked fuel pressure yesterday and it looks good. Checked 35 psi and held the pressure good with engine shut off. Removed gauge after about 15 minutes or so. Manual states that fuel pressure should be between 30 to 40 psi and hold this pressure with engine off for at least 5 minutes. It's looking like I might have to drop the tank to find this problem. I'm guessing that it is loosing fuel pressure after setting for 8 hours or so and some how getting air in the line. Any Idea's or suggestions out there?

One thing I forgot to mention in the first message is that I cleaned the mass air flow sensor changed to a new air filter reset the code error and the engine light comes back on with the same P0102 fault. Checked the PID'S and the MAF stays at 9 sec and never changes no matter what RPM you are running at. Is this normal? I would think it would change? Should I replace the MAF sensor? I also have removed the EGR valve and cleaned it and the port it bolts to. I have not done anything to the EGR pressure sensor.