91 PA Poor acceleration

I have a 1991 Buick Park Avenue that I let sit for 6 months. When I tried to drive it, it accelerates very poorly. I took it to my mechanic and he changed the sparg plugs and wires, but it still had problems. I tried a different electronic ignition module (junk yard part), but still have the same problems. I can take it out on the freeway and it will go up to 90 mph but it takes a long time to get there. I have gone thru 2 tanks of gas so I doubt it's bad gas. There are no error codes present when I install a jumper on the board and read the flashing check engine lights. Anyone out there have any ideas???

It sounds very much to me like you need to replace your fuel filter. It also could be that you need your injectors pressure cleaned.

Thanks for responding. I'll try the fuel filter 1st.