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/InstallationRefrigerant Pressure Sensor Removal/Installation [Manual Air Conditioner]
1. Disconnect the negative battery cable..
2. Discharge the refrigerant..
3. Disconnect the refrigerant pressure sensor connector.
CAUTION:
If moisture or foreign material enters the refrigeration cycle, cooling ability
will be lowered and abnormal noise will occur. Always immediate ...
Room Light Control System
Outline
The room light control system changes the illumination condition and illumination
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Clutch Master Cylinder Removal/Installation [C66 M R]
CAUTION:
Secure the steering wheel using tape or a cable to prevent the steering shaft
from rotating after disconnecting the steering shaft. If the steering wheel
rotates after the steering shaft and the steering gear and linkage are disconnected,
the internal parts of the clock spr ...