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/InstallationNon Return Valve Inspection
WARNING:
Fuel is very flammable liquid. If fuel spills or leaks from the pressurized
fuel system, it will cause serious injury or death and facility breakage. Fuel
can also irritate skin and eyes. To prevent this, always complete the “Fuel
Line Safety Procedure”, while referring ...
Security Indicator Light
Purpose
Notifies the driver that the immobilizer system is operating.
Function
If a malfunction is detected in the immobilizer system, the DTC can be verified
by the flashing pattern of the security indicator light.
Construction
The security indicator light is bui ...
Customer Assistance (Puerto Rico)
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