CRC Industries Top Engine Cleaner, No. 05312, cleans carbon deposits that collect on the intake manifolds, intake valves and on other residue in the engine without special tools. Meant to be an aftermarket solution to otherwise OE-specific top end cleaners, this product helps maximize efficiency and power when used regularly. By simply using the attached extension tube, the chemical can be sprayed directly into the throttle body while the engine is idling at around 2,000 rpm. After this, the engine should be turned off and the chemical allowed to heat-soak for 15 to 20 minutes. The car can be simply driven afterwards.