Hi Matt - I did what you suggested but can't find anything. I've noticed a warning on the engine regarding damaging the cat in relation to overfilling the oil which I did (and have done on several occasions). Could it be the cat on the way out as I've haven't renewed it in 350K?!! It has also got a valeo replacement clutch with single mass flywheel which has covered 80k - could it be the release bearing? Many thanks.