Hi [...] fleet of Ford E-vans is starting to have Clogged egr ports,resulting in missfires on cyl.'s 3 or 6. The one Today is a 2001 E-250 with 4.2 v6. DTC po303 set. The engine missfires when egr is applied.I know about the plugged egr passages, bur haven't y... Login to read more.