Purpose, Function
Piston
The piston in the cylinder of the cylinder block moves reciprocally by the pressure received when the air-fuel mixture combusts.
Piston ring
The piston ring consists of the compression ring (top ring, second ring) and the oil ring, and has the following function.
The compression ring prevents leakage of pressure in the cylinder from the piston circumference.
The oil ring clears off extra engine oil adhered to the cylinder wall.
The piston ring transmits piston heat to the cylinder wall to cool the piston.
Piston pin
The reciprocating movement of the piston is transmitted to the connecting rod by the connection of the piston pin to connecting rod.
Construction
Piston
The high-temperature strength piston is made of aluminum alloy with excellent thermal conductivity.
The piston has a cavity on the top surface. As a result, the initial combustion flame is prevented from hitting the top surface of the piston to reduce cooling loss.


The sliding resistance has been reduced by optimizing the piston skirt shape.
A weight reduction is realized by optimizing the piston shape.
With the adoption of the offset piston, piston slap is suppressed.

Piston ring
A barrel-face ring for the top ring and a taper under cut ring for the second ring have been adopted.
A three-piece oil ring consisting of a side rail and spacer have been adopted for the oil ring.
Tracking capability to the cylinder wall has been improved by thinning down the piston ring. As a result, a low-tension piston ring has been implemented without increasing the engine oil consumption, and the sliding resistance has been reduced during reciprocating movement.
Piston pin
The piston is a full-floating type.
Connecting Rod, Connecting Rod BearingDown Switch [Fw6 A EL, Fw6 Ax EL]
Purpose/Function
The down switch detects the shift down operation of the selector lever.
The down switch signal is sent to the TCM via CAN and is used for manual
shift control and engine-transaxle integration control.
Construction
The down switch is installed to the se ...
Brake/Clutch Fluid
Inspecting Brake/Clutch Fluid Level
The brakes and clutch draw fluid from the same reservoir.
Inspect the fluid level in the reservoir regularly. It should be kept at MAX.
The level normally drops with accumulated distance, a condition associated with
wear of brake and clutch linings. If it is ...
Tcs/DSC Indicator Light
Purpose/Function
The TCS/DSC indicator light, built into the instrument cluster, informs the
driver of the following vehicle conditions.
TCS is operating. (Drive wheel is slipping.)
DSC is operating. (Vehicle side-slip condition.)
Roll over mitigation (RO ...