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/InstallationStarter Interlock Switch [Skyactiv G 2.0]
Purpose, Function
The starter interlock switch mechanism prevents vehicle surge when the engine
is started, enhancing safety. The engine cannot be started unless the clutch
is depressed.
Construction
The mechanism is provided with a starter interlock switch on the circuit
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License Plate Light Bulb Removal/Installation
1. Disconnect the negative battery cable..
2. Insert a tape-wrapped flathead screwdriver into the clearance between the
lens and license plate light shown in the figure.
3. Move the flathead screwdriver in the direction of the arrow shown in the figure,
pull out the lens from the license ...
Light Switch Inspection
Light Switch
1. Disconnect the negative battery cable..
2. Remove the column cover..
3. Remove the light switch..
4. Verify that the continuity between the light switch terminals is as indicated
in the table.
Vehicles without auto light system
Vehicles with auto light system
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