EXHAUST GAS RECIRCULATION SYSTEM [SKYACTIV-X 2.0]

id0116hf159300


Exhaust Gas Purification System


Purpose, outline

•  The system recirculates the high-temperature exhaust gas to the combustion chamber and lowers the temperature in the combustion chamber. The following is achieved by recirculating the exhaust gas.
―  Fuel economy and NV performance have been improved by reducing pumping loss, reducing cooling loss, and suppressing temperature increases in the combustion chamber and knocking.
•  To perform optimum control according to the engine operation conditions, the EGR valve is opened and the exhaust gas is recirculated based on the information such as the exhaust gas pressure just after it passes through the EGR cooler.


Structure

System diagram

am3zzn00010346

Part name

Reference
EGR valve
(See EGR valve.)
EGR cooler
(See EGR cooler.)
Exhaust shutter valve*1
(See Exhaust shutter valve (Australian, European (L.H.D. U.K.) specs.).)

*1  :Australian, European (L.H.D. U.K.) specs.


Operation

•  The operation of the exhaust gas recirculation system is as follows.

1.  The exhaust gas just after combustion is cooled by the EGR cooler.

2.  The exhaust gas passing through the EGR valve is recirculated upstream (intake manifold) of the combustion chamber.

•  For EGR control details, refer to CONTROL SYSTEM. (See EGR CONTROL [SKYACTIV-X 2.0].)


EGR valve


Purpose, Function

•  The EGR valve adjusts the amount of exhaust gas passing through the EGR cooler to be recirculated to the intake manifold.
•  The EGR valve opens/closes the valve according to the control signal from the PCM.


Construction

•  The EGR valve is located on the downstream side of the EGR cooler.
am3zzn00009705
•  The EGR valve has adopted a DC motor.
•  The EGR valve is built into the EGR valve position sensor.


Operation

•  The EGR valve is opened to the valve opening angle according to the energization current flowing to the DC motor from the PCM.
am3zzn00010285


EGR cooler


Purpose, Function

•  The EGR cooler cools the exhaust gas recirculated to the intake manifold using the engine coolant.
•  The temperature in the combustion chamber is effectively decreased by cooling the recirculated exhaust gas.


Construction

•  The EGR cooler is located near the intake manifold.
am3zzn00009705
•  The EGR cooler consists of the exhaust gas passage and engine coolant passage.
•  Plate-type fins have been adopted for the engine coolant passage fins.
•  The exhaust gas flowing from the catalytic converter is cooled in the EGR cooler and flows to the EGR valve. The exhaust gas passing through the EGR valve recirculates to the intake manifold.
atsuzn00000927


Exhaust shutter valve (Australian, European (L.H.D. U.K.) specs.)


Purpose, Function

•  The exhaust shutter valve adjusts the exhaust gas amount recirculated from the exhaust valve into the cylinder to increase the gas temperature in the cylinder.


Construction

•  The exhaust shutter valve is located in the exhaust pipe.
atsuzn00000870
•  The exhaust shutter valve consists of the exhaust shutter valve position sensor, DC motor, valve shaft, and valve.
am3zzn00009711
•  The exhaust shutter valve has an integrated exhaust shutter valve position sensor. For details on the exhaust shutter valve position sensor, refer to the CONTROL SYSTEM. (See EXHAUST SHUTTER VALVE POSITION SENSOR [SKYACTIV-X 2.0].)


Operation

•  The EGR valve is opened to the valve opening angle according to the energization current flowing to the DC motor from the PCM.
atsuzn00000956