Duratorq-TDCi Exhaust Gas Recirculation System (EGR)
The EGR system is used to reduce the levels of NOX produced during combustion of diesel fuel in the combustion chamber, particularly at light load and during cruise. During operation a portion of the exhaust gas is re-circulated via the EGR valve back into the system into the incoming air flow in the inlet manifold.
The introduction of exhaust gas into the intake stream reduces the combustion temperatures, which in turn lowers the NOX levels in the exhaust stream.
The EGR rate is dependent on engine load and operating conditions, but is particularly efficient in the low load / low RPM range.
When the EGR system is active, exhaust gas passes from the exhaust stream through the EGR cooler, or is bypassed depending on the position of the EGR cooler bypass valve and into the intake stream.