Liqui Moly Jectron Gasoline System Cleaner, 300 ml, Liqui Moly part number 2007. Deposit-related symptoms build gradually and affect all cylinders together. On direct injection BMW engines, intake valve deposits form on the port side where fuel never touches them, so a fuel-borne cleaner treats the injectors and combustion chamber but cannot clean the intake valves; that job needs walnut blasting.
