Ford Aerostar :: 1995 - Runs And Idles Rough After Sitting 10 Days?

So I have a 95 aerostar 3.0. I use it every day my a delivery vehicle. I keep it maintained. About a month that ago, it developed a skip or a hesitation, most!y at high speeds, usually under load. I thought it may be transmission but had it checked and was ok. I drove it like that for several weeks. Then got worse so I parked it for ten days until my mechanic was available. When I cranked it to drive it over, it spit and sputtered the whole way here and barely made it. It had never done that before. He changed plugs and wires and distributor cap, even though it had been less than a year since all that had been done. Still no change. Driving way worse after sitting for ten days.