1998 ford f150 xlt 4.6 l back fires on start up rough idle wants to shut off replace IAT Mass airflow sensor Cam shaft sensor Crank shaft sensor installed new plugs still backfires rough idle and wants to die What could be the problem?

What is your question?

1998 Ford f150 4.6£ Back fires on start up rough idle have to give it throttle or it will die intermittently back firing Changed the IAT sensor Mass air flow sensor Camshaft sensor Crankshaft sensor installed new plugs still has the same problem What could be the problem?

What makes this problem better or worse?

Doesn't change for the better or worse

How long has your 1998 Ford F-150 had this problem?

Had to have new keys made and programmed that's when it started