surging 5.0

[neilk]

Hi, newbee looking for help, I have a 98 Ranger with a Explorer 5.0 in it and a M5OD behind it. I have been fighting this problem for a year, I have a intermitent engine surge it typically happens right after or while I am climbing a hill. All of a sudden out of nowhere it will start surging under a load it idles fine, Here is what I have done, Read the codes, nothing I don't expect there, blocked off the egr, changed TP sensor, changed mass air, changed cam sensor ,disabled evap just in case it isn't venting properly, changed coil packs, check all the vacuum circuits, funny thing is it will disappear within a day usually and be gone for a long time, I even tried unhooking the battery thinking maybe the ecu doesn't like the fact there isn't an aod in it,the other thing is it never has happened during the summer, I am at a total loose here I need a new set of eyes and there really isn't anyone around my area that can or wants to help because of the engine swap....thanks for any ideas you can come up with,,,Neil