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/InstallationHood Latch Switch Inspection
1. Disconnect the negative battery cable..
2. Remove the front bumper..
3. Disconnect the hood latch switch connector..
4. Verify that the continuity is as indicated in the table.
NOTE:
Inspect the continuity when the hood is open and closed.
If the operation as i ...
Front Lower Arm Inspection
1. Remove the front lower arm..
2. Inspect the front lower arm for bending or damage, and the front lower arm
ball joint for excessive looseness.
If there is any malfunction, replace the front lower arm.
3. Rotate the front lower arm ball joint stud 5 times. Install the
SST ...
Intake Air Temperature (Iat) Sensor Inspection
IAT Sensor No.1
Resistance inspection
NOTE:
Because the IAT sensor No.1 is integrated in the MAF sensor, replacing the
IAT sensor No.1 includes replacement of the MAF sensor/IAT sensor No.1.
1. Disconnect the negative battery cable..
2. Disconnect the MAF sensor/IAT sensor No.1 ...