Intake valve cleaning method for a direct injection engine with computer controlled intake valves

摘要

A method for a vehicle traveling on the road having an engine with adjustable valve operation is described. The method includes performing a valve cleaning operation for reducing deposits on a valve of the engine; and at least during said operation, adjusting valve timing of at least a valve of the engine and a fuel injection amount to increase an amount of fuel pushed back from a cylinder past the valve with deposits and then re-inducted through the valve with deposits.