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/InstallationParking Brake Lever Removal/Installation
1. Remove the front console box..
2. Remove the shift lever knob. (MTX).
3. Remove the shift panel..
4. Remove the upper panel..
5. Remove in the order indicated in the table.
6. Install in the reverse order of removal.
7. After installation, inspect the parking brake lever stroke..
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Rear Upper Arm Removal/Installation [Awd]
WARNING:
Verify that the crossmember is securely supported by a jack. If the rear
crossmember falls off, it can cause serious injury or death, and damage to the
vehicle.
CAUTION:
Performing the following procedures without first removing the rear ABS wheel-speed
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D Pillar Speaker Removal/Installation
1. Disconnect the negative battery cable..
2. Remove the following parts:
a. Trunk board.
b. Trunk end trim.
c. Rear scuff plate.
d. Trunk side trim.
e. D-pillar trim.
3. Disconnect the connector.
4. Remove the screws.
5. Remove the D-pillar speaker.
6. While pressing the tab ...