Method for controlling exhaust gas after treatment for internal combustion engine, involves supplying coolant to reducing agent injection valve depending on temperature of reducing agent injection valve

摘要

The method involves supplying a coolant to a reducing agent injection valve (64) depending on a temperature of the reducing agent injection valve, which is formed in an exhaust manifold (14) for cooling the reducing agent injection valve. The reducing agent injection valve is formed in the exhaust manifold upstream to the selective catalytic reduction-catalytic converter (34) of an internal combustion engine and for measuring the reducing agent in the exhaust manifold. The nitrogen oxides content in the exhaust manifold is determined.