I have a 99 Expedition. It seems to have the same problem as many others. It puts out code PO303. It is mainly affected in the RPM range 1400 to 1600. Seems to idle fine. It come out of the hole with a miss here and there. I have not changed anything yet. I have been reading these forums only to get more confused on what might be the problem. I,m hoping someone can shead some light on the subject for me. Thanks, Ken.