All engines develop performance issues over time, whether they're gas, diesel or ethanol. Carbon deposits reduce performance and fuel economy. Water and ethanol corrode key engine parts. Gumout Multi-System Tune-Up is the most advanced treatment for all types of engines, from cars to lawn mowers. It cleans and conditions using premium ingredients, like PEA (polyether-amine), to help maximize performance, fuel economy and engine life. Multi-System Tune-Up can be added in the gas tank, the crankcase or via induction.