The battery supplies the power necessary to start the engine when the ignition switch is is turned on.

Constant velocity (CV) joints are located at both ends of a half shaft and their purpose is to transfer the torque from the transmission to the drive wheels at a constant speed while accomodating the up and down movement of the suspension. The inner CV joint connects the shaft to the transmission and the outer CV joint connects the shaft to the wheel.

The fuel injector sprays fuel into the air stream that's being fed into the cylinder head via the intake valve. The timing and amount of fuel are regulated by the powertrain control module (PCM) which is the main computer that controls engine and transmission functions.

The muffler follows the catalytic converter and absorbs sound to help quiet load exhaust. It is followed by the exhaust pipe which is the final exit point for exhaust gas from the vehicle.

Because a compressed spring will ex­tend violently, shock absorbers must be used to dampen the spring’s compression and extension cycles. Struts combine the spring and shock into one unit