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/InstallationRear ABS Wheel Speed Sensor Inspection [Awd]
Installation Visual Inspection
1. Inspect the following items:
If there is any malfunction, replace the applicable part.
a. Excessive play of the ABS wheel-speed sensor
b. Deformation of the ABS wheel-speed sensor
c. Deformation or damage of the ABS sensor rotor
Clearance Inspec ...
Auxiliary Jack/Usb Port Inspection
Auxiliary jack inspection
1. Disconnect the negative battery cable..
2. Remove the following parts:
a. Upper console.
b. Auxiliary jack/USB port.
3. Connect a commercially-available plug to the external input unit.
4. Verify that the continuity between the external input unit terminal ...
Clutch Cover Inspection [C66 M R]
1. Remove the clutch cover..
2. Perform the following procedures to inspect the clutch cover.
If it exceeds the maximum specification, replace the clutch cover..
a. Measure the wear of the diaphragm spring fingers.
Clutch cover diaphragm spring fingers maximum depth
0.6 ...