So it continues... Fitted a new coilpack, ticks over much more smoothly now. However, misfire under load is still there!!! I have also tried a new fuel pump relay, had to wait for the old one to cool before I could remove it - it was hot, hot, hot (Is that normal?) Strange thing is that it wouldn't run with the new relay. I've exchanged it, but not tried it yet, I'll keep you all posted. Thanks again for all of the ideas etc.