With STARTER SPRAY, starting up your car engine will never be a problem again. At any temperature or degree of humidity, STARTER SPRAY is ideal for gasoline, natural gas, or diesel engines. Lubricates, but does not corrode the engine. Prolongs engine and battery life. INSTRUCTIONS FOR USE: shake cylinder well before using. Gasoline or natural gas engines: spray two or three times into the air filter vent, then start the car immediately up and accelerate slightly. Diesel engines: spray into the air filter while starting the car up and continue until the engine has caught.