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/InstallationBlind Spot Monitoring (Bsm) System
Outline
The blind spot monitoring (BSM) system detects vehicles approaching from
the rear blind spots, and illuminates the BSM indicator light on the outer mirror
glass. When the BSM indicator light is illuminated and the turn light switch
is turned on to the side in which the indica ...
Rear Bumper Reinforcement Removal/Installation
1. Disconnect the negative battery cable..
2. Remove the following parts:
a. Rear splash shield.
b. Rear combination light.
c. Rear bumper.
3. Remove the hanger rubber in the direction of the arrow (1) shown in the figure.
4. Remove nuts.
CAUTION:
Removing the rear bumper ...
Starter Removal/Installation [Skyactiv G 2.0]
WARNING:
Remove and install all parts when the engine is cold, otherwise they can
cause severe burns or serious injury.
When the battery cables are connected, touching the vehicle body with starter
terminal B will generate sparks. This can cause personal injury, fire, and d ...