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/InstallationPressure Sensor Removal/Installation [Two Step Deployment Control System]
WARNING:
Handling the pressure sensor improperly can accidentally operate (deploy)
the air bag module, which may seriously injure you. Read the air bag system
service warnings and cautions before handling the pressure sensor..
1. Switch the ignition to off.
2. Disconnect the ne ...
Engine Oil Pressure Warning Light
Purpose
The engine oil pressure warning light warns the driver that the engine oil
level is insufficient.
Function
When the instrument cluster receives the engine oil pressure warning light
request signal sent from the PCM via the CAN signal, it illuminates the engine
oi ...
Engine Transaxle Integration Control [Fw6 A EL, Fw6 Ax EL]
Outline
The TCM controls engine output torque and reduces transaxle output shaft
torque fluctuation during auto shifting, and reduces shock occurring from the
vehicle during shifting.
Construction
Operation
During auto shifting, the TCM sends the torque reduction reque ...