Thanks guys.
Darren (mortygttdi) came round about an hour ago and checked out the car and it was an emissions problem. The light is cleared so we'll see how it goes. If the light comes back on at least I know what the problem is. Airbag light is also out now too
A big thanks to Darren for coming round at such short notice. He also spotted that my car has electric folding mirrors which I hadn't even noticed
Now to sort the sideskirt, and the wheel noises...