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/InstallationPower Window System Preliminary Inspection [Power Window System]
Manual Open/Close Function Inspection
STEP
INSPECTION
ACTION
1
Switch the ignition ON (engine off or on).
Operate the power window using the manual open/close function on
the power window main swit ...
Service Cautions
Injury/damage Prevention Precautions
Depending on the vehicle, the cooling fan may operate suddenly even when
the ignition is switched to off. Therefore, keep hands and tools away from the
cooling fan even if the cooling fan is not operating to prevent injury to personnel
or damage t ...
Bsm Indicator Light Flashes While Not Under Bsm Indicator Light Flashing Conditions
(No Combination Switch Operation (Turn Signal Switch)) [Blind Spot Monitoring (Bsm)]
Description
BSM indicator light flashes while not under BSM indicator light-flashing
conditions (no combination switch operation (turn signal switch)
The BSM indicator light flashes despite not satisfying the BSM indicator
light flashing ...