This stuff is great!! My 2013 Nissan Navara D40 has only travelled 50,000km but has been idling roughly, a little rattly and lagging in acceleration when I put my foot down. I put it all down to it being a CR diesel. After one use of this product the idling smoothed out, acceleration was responsive like never before and the rattling CR diesel noise was gone…all in 5 minutes! I have since treated my 2016 Hayabusa motorcycle and reel mower – all run more smoothly and quieter. Thanks to Fuel Doctor I know my engine fuel systems are tip top. Can’t overrate this product!!