Exhaust gas recirculation apparatus for engine with turbocharger

摘要

An exhaust gas recirculation controlling apparatus suitable for an engine wth a turbocharger. An EGR valve which is provided in an EGR passage connecting an exhaust system passage and an intake system passage of the engine controls the amount of EGR. A vacuum adjustment valve controls the vacuum supplied from a vacuum source to the EGR valve. A valve device for cutting off the supply of vacuum in a vacuum range which is lower than the vacuum corresponding to at least the lower limitation value in the EGR controlling range with respect to the vacuum controlling characteristics of a vacuum adjustment valve is provided in the passage connecting the EGR valve and the vacuum adjustment valve such as to securely close the EGR valve when the running state of the engine is out of the EGR controlling range.