Well i gave ford a quick ring, and they guy reset it for me for free so they aernt all bad.

Disconnecting the battery did get rid of the light if i left it off for a couple of mins, but the codes are remembered. The guy cleared everything with his little computer.

I think the problem may have been caused by me not pushing the MAF plug on fully after fiddling about the other day seeing as i was hanging off when i opened the bonnet up.

Really should check everything properly after taking things apart.