A fluid for cleaning and decarbonizing internal combustion engines is aerosol sprayed into the air intake system and throttle body then scrubbed. The fluid comprises (1) 45 to 55 percent by weight of Acetone, Chemical Abstract Service Registry Number 67641; (2) 25 to 35 percent by weight of Butyl Cellosolve, Chemical Abstract Service Registry Number 000111-76-2; (3) 8 to 12 percent by weight of Benzyl Alcohol, Chemical Abstract Service Registry Number 100-51-6; (4) 3 to 7 percent by weight of Propylene Glycol, Chemical Abstract Service Registry Number 000057-55-6; (5) 3 to 5 percent by weight of Ethylene Glycol, Chemical Abstract Service Registry Number 000107-21-1; (6) 0.8 to 1.2 percent of Polyol Ester, Chemical Abstract Service Registry Number 11138-60-6; and (7) generally 1 to 5 percent by weight of Carbon Dioxide, Chemical Abstract Service Registry Number 128-38-9.