Hi, My lovely little Copen suddenly lit it's engine warning light (looks like a little orange engine) last August. I took it straight to the main dealer who told me it was an engine misfire and to replace all the spark plugs. I did that and all was well until around May when it came on again. I had it checked again and it said it was the O2 sensor, bank 1 sensor 1. I changed it and the light went out...... then it came on ....... then it went off .... and so on. It's currently off again. I've had the error codes checked and they say: P0135 O2 sensor bank 1 sensor 1 (I've already replaced that) P0300 Random Multiple Cylinder Misfire detected P0301 Cylinder 1 misfire detected P0302 Cylinder 2 misfire detected P0303 Cylinder 3 misfire detected P0304 Cylinder 4 misfire detected. Anyone have any advice?