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/InstallationLap Pre Tensioner Seat Belt [Two Step Deployment Control System]
Purpose
The lap pre-tensioner seat belts retract and tighten the seat belt webbing
to protect the front passengers during a collision.
Function
The lap pre-tensioner seat belts operate (deploy) based on the operation
signal from the SAS control module to instantly retract a ...
Starter 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
...
Power Windows
The ignition must be switched ON for the power windows to operate.
WARNING
Make sure the opening is clear before closing a window:
Closing power windows are dangerous. A person's hands, head, or even neck could
be caught by the window and result in serious injury or even death. This warning ...