I added a bottle of BMW Group's Fuel System Cleaner Plus, it's really just overpriced Chevron Techron, to my latest fill-up in an effort to ensure my fuel system will run smoothly until I get around to changing the fuel filter and other parts. I exclusively pump Shell V-Power Nitrogen Enriched fuel 91 octane, which already contains, in my opinion, the best additive and cleaners, but it never hurts to be "sure".
