Purpose, Function
By lengthening the exhaust passage, the transmission of exhaust pressure waves to other cylinders can be delayed, and the amount of gas exhausted from a cylinder and forced back inside the combustion chamber is reduced By reducing the residual gas, the temperature inside the combustion chamber is reduced and the occurrence of knocking even at a high compression ratio is inhibited.
Construction
The exhaust manifold is installed to the rear of the engine. In addition, the catalytic converter (WU-TWC) is integrated (WU-TWC).

When the No.1 cylinder is at the intake stroke, the No.3 cylinder is at the exhaust stroke. By inducing the high temperature gas exhausted from the No.3 cylinder into the No.1 cylinder, the high temperature gas in the No.1 cylinder remains. If the amount of residual gas is high, the temperature in the combustion chamber rises and knocking can easily occur. With the 4-2-1 exhaust system, the transmission of exhaust pressure waves between each cylinder is delayed by the long exhaust pipes.

Exhaust System Removal/InstallationTorque Sensor
Purpose/ Function
The torque sensor detects the steering torque and the steering direction,
and outputs the signal to the Electric Power Steering (EPS) control module (CM).
Construction, Operation
The Hall IC-type torque sensor is installed to the top of the steering column
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Ignition Coil/Ion Sensor Removal/Installation [Skyactiv G 2.0]
1. Disconnect the negative battery cable..
2. Remove the plug hole plate..
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
1
Connector
2
Ignition coil
...
Rear Body Straight Line Dimensions (1) [Dimensions]
Point symbol
Designation
Hole diameter or bolt or nut size mm {in}
A
Liftgate hinge installation hole
?12 {0.47}
B
Liftgate stay damper installation hole
?10 {0.39}
...