Engine size or all all 16V Zetecs the same? Try uk.rec.cars.maintenance as
you may find more people there with an interest in Fords.

I know it has just had plugs and leads but check them again - usually
3 & 4 for any black lines up the ceramic & also inside the leads -
without silicon grease they don`t last very long as there is about
60,000 volts produced by these coil packs - also check the T piece on
the cylinder head under the coil pack on the vacuum side for signs of
collapse or holes - also these engines will run lumpy when cold if the
wrong engine oil is used and sometimes when hot also - it should be
running on 5w30.
The things i have listed are the usual faults - we get very few faults
with anything else on this model !
Hope this helps
                           Mike D.