I had same problems with hard acceleration and almost stalling at idle light would come on. I noticed my spark plugs had a huge gap of over .040 so I put in new NKG and gapped at .032 and light now is not coming on. Idle is still rough but not almost stalling as before. I think I have to clean contacts on AFM. But rough idle seems to be a common problem on M30.....Has anyone with 535 have a smooth idle?????????????