Zetec 2002 spark plug Gap

[Kipper31]

Hi just confirming spark plugs gap.Wife's car has had a intermittent miss so we changed spark plugs first.They gave us the same as I took out and noticed the gap was 1.3 but the book states 1.00. Not concerned as it ran well with the 1.3 for 40,000 km.Car ran heaps smoother but today was still missing again and lagging under load.Im thinking of doing the coil pack next and leads as there both quite cheap.Any ideas what the intermittent miss could be.Cars done around 90000 km.Thanks Chris