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/InstallationCheck Valve Removal/Installation
Except U.S.A. And CANADA
1. Remove the floor under cover..
2. Remove in the order indicated in the table.
1
Evaporative hose
2
Check valve
3. Install in the reverse order of removal. ...
Camshaft Position (CMP) Sensor Removal/Installation
CAUTION:
When replacing the CMP sensor, make sure there is no foreign material on
it such as metal shavings. If it is installed with foreign material, the sensor
output signal will malfunction resulting from fluctuation in magnetic flux and
cause a deterioration in engine control.
...
Wheel Apron Component Installation [Panel Replacement]
Symbol Mark
Installation Procedure
1. When installing new parts, measure and adjust the body as necessary to conform
with standard dimensions.
2. Drill holes for the plug welding before installing the new parts.
3. After temporarily installing new parts, make sure the related parts fit p ...