Never tried anything yet. Searched high and low locally for the Amsoil cetane boost with no luck. I am not really experienced with diesels. Had a Frog .15 as a kid that I never could start. A friend got it going, but I never could. Have a PAW .06 now and the Cox head that I would like to give a go, but need to go through a learning curve before I could make any statements. A bit busy with a move now too.