Loosen/ remove the gas cap. Will it run then?
If not, check your fuel pressure, should be a schrader port just towards the front engine side of the alternator pulley on the end of the rear fuel rail. What is the pressure at prime? At engine idle?
Could be a bad ICM. Does it loose spark when it acts up? Will it start with some starting fluid when it is non starting?
Also will it start with the MAF unplugged? If so the MAF could be bad (I JUST found a loose connection on my connector for mine - of course I have a scantool with a live data mode so I saw it jump.)