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/InstallationMass Air Flow (MAF) Sensor Inspection
Visual Inspection
1. Remove the MAF sensor/IAT sensor No.1..
2. Visually inspect the MAF sensor for the following:
Damage, cracks, soiling
Rusted sensor terminal
Bent sensor terminal
If there is any malfunction, repair or replace the MAF sensor/IAT sensor
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Push Button Start Removal/Installation
1. Disconnect the negative battery cable..
2. Remove the meter hood..
3. While pressing the push button start tab in the direction of the arrow (1)
shown in the figure, push out the push button start in the direction of the arrow
(2) shown in the figure to detach the push button start tab fr ...
Condenser Inspection
1. Inspect the condenser for cracks, damage, and oil leakage.
If there is any malfunction, replace the condenser.
2. Visually inspect for bent fins for clogging of foreign material.
If any fins are clogged, remove the foreign material.
3. Visually inspect for bent fins.
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