most likely it is the timing belt hitting the cover. This normally only happens when the car is cold. there is alot of information on this in the zetec forum if you search. This is a fairly normal and frequent amoung the cars. you can either take the cover off, put washers in as spacers or live with the problem, your choice
Son - 1995 Mystique LS Zetec 5-spd --> newest "mod" -> a girlfriend by my side
Father - 1995 Contour SE Duratec 5-spd
Mother - 1999 Contour SE Sport Duratec 5-spd
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