Internal combustion engine having lean nox catalyst

Abstract

An internal combustion engine having a lean NOx catalyst is capable of relieving a load upon an engine fuel injection device by eliminating the use of sub-injection, and of well purifying an exhaust gas and recovering from S-poisoning even by eliminating the use of the sub-injection. The internal combustion engine has a combustion heater for allowing a flow of combustion gas through an engine intake passageway to raise temperatures of engine related elements, a lean NOx catalyst, provided in an engine exhaust passageway, for purifying an engine exhaust gas, and a combustion gas introducing passageway for introducing at least some proportion of a combustion gas emitted by the combustion heater, toward upstream of the lean NOx catalyst in the engine exhaust passageway from the engine intake passageway when making a request for a reproducing process of the lean NOx catalyst.

Dependencies are inferred from the claim text.