Internal combustion engine fuel/air mixture control procedure includes increase in charge fed to one group of cylinders at low load to accelerate heating of pollution reducer

摘要

The procedure, for use especially with a petrol or Diesel engine having at least two groups of cylinders (12, 14), and an exhaust pipe (40) with at least one pollution reduction unit (42), consists of evaluating the total charge admitted into the engine during operation at low speeds and/or torque and allowing a greater proportion into one group of cylinders (12) than the other (14). The charge can be taken as the amount of fuel injected into the cylinders or the quantity of the fuel/air mixture, and the larger proportion can be e.g. 75 per cent, designed to increase the exhaust gas temperature and speed up the heating of the pollution reduction unit.