99 S80 Engine turns but doesn't start.

[corkyspotspaz]

I REALLY NEED SOME HELP!! I bought a 1999 S80 and one week after I bought it the driver wheel fell out of the ball joint and A-Arm....got that fixed and then my check engine light came on. No big deal just turned out to be a gas cap leak. So then my check engine light comes on and my acceleration has major hesitation.....push in the foot pedal and it takes like 5 seconds for the car to take any action. So lets just say if I were to try to make it off the starting line I'd be left in the dust. And when I am coming to a stop, the automatic down shift pushes forward hard. Kinda sends u flying forward in a burst. And while these things are all happening my service engine came on and the idle likes to bounce from 0-7 in park or nuetral. It does it in drive too but not as severe. So now I was driving it and it just putts itself till it dies quickly. So I took it in and it gave a P1 code for the mass air flow censor. So we changed it with another that we had in the lot, and it ran fine all night. Then went to start it the next morning and it turns or cranks but doesn't start. So now I don't know what to do. Please if someone can help I would like to know if its a Fuel issue or something more serious.