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/InstallationCoupling Component Removal/Installation
WARNING:
When replacing the coupling component, read the special character string
before installing a new coupling component and write it to the AWD control module
after replacement. The special character string is indicated in the two locations
shown in the figure.
1. D ...
High Clutch [Fw6 A EL, Fw6 Ax EL]
Purpose/Function
The high clutch operates in 4GR, 5GR, and 6GR and intermittently operates
the rear carrier by drive force from the turbine shaft.
For the high clutch, a centrifugal balance clutch has been adopted to prevent
clutch drag and to assure stabilized piston thrust in ...
Washer Nozzle
Purpose
The washer nozzle sprays the washer fluid sent from the washer motor to the
optimum positions on the windshield.
Construction
A ball-shaped spray orifice is set inside the washer nozzle which can be
adjusted up or down.
The washer nozzle is moved u ...