EGR System Description - Overview (2014 2015)
The EGR system lowers combustion temperature and reduces oxides of nitrogen (NOx) emissions, the EGR cooler further cools hot EGR gas.
The recirculating exhaust gas routes through the EGR pipe, the EGR cooler, the intake manifold, and into the combustion chambers. Routing the exhaust gas through the EGR pipe helps to prevent carbon deposits from forming in the intake manifold and the throttle body.
The PCM memory includes the ideal EGR valve position for varying operating conditions.
The EGR valve position sensor detects the amount of EGR valve lift and sends it to the PCM. The PCM then compares it with the ideal lift in its memory (based on signals sent from other sensors). If there is any difference between the two, the PCM cuts power to the EGR valve.
Exhaust Gas Recirculation Flow
The exhaust gas downstream of the warm up three-way catalytic converter (WU-TWC) flows through the EGR pipe, the EGR cooler, the passage in the cylinder head, and the exhaust gas recirculation or EGR valve and position sensor.
EGR Valve
The EGR valve consists of the following components.