2004 mpv running rough
 

i have a 2004 mpv, and it was running rough, like when i excelerate it would hesitate and jump really bad, so i had a tune up on it, they replaced all the spark plugs, and it still ran rough. they put new catlytic cnv. on it and new manifolds and replaced 2 coil packs and changed out 2 of the vacuum hoses. and it is still running bad, does anyone have any suggestions on what else it could be. i already put $2000 into it. HELP