01 E150 no acceleration

my companies van has a problem with, firstly, going to start it. It takes 2-3 tries to get it to start. Its not like that battery it dead, it turns over but doesn't start. Secondly, if you hold the accelerator down any farther than a 1/4" its starts dieing. You can hold the pedal all the way down and in a few seconds its snap out of it. Thirdly, if i'm so lucky to get it up to speed, it won't hold a speed, it just starts dieing. Any suggestions?

It sounds like you may be losing fuel pressure. When was the fuel filter changed last? If it hasn't been replaced in a long time, it may be plugged, preventing adequate fuel flow.