Controlling secondary air feed to internal combustion engine exhaust system, involves delivering secondary air via throughflow control valve with opening controlled in synchronism with crankshaft angle

摘要

The method involves delivering the secondary air via a throughflow control valve whose opening is controlled in synchronism with the crankshaft angle. The throughflow control valve is controlled in synchronism with the crankshaft angle during the vacuum stage of a pressure pulse during the exhaust phase. The throughflow control valve can be controlled to open several times per crankshaft revolution.