The main computer or powertrain control module (PCM) uses pre-programmed software to analyze the input received from sensors and produce output signals to adjust vehicle performance and operation. (Engine control unit (ECU) is another name for the PCM.)

A v-arrangement has two rows of cylinders in a V-shaped block with a crankshaft at the bottom of the V. Any even number of cylinders is possible in this configuration from the V-2 that's commonly used in motorcycles up to V-12 or bigger for large trucks. The V design produces a shorter engine than an in-line cylinder configuration and allows for better air-fuel distribution.

An inline cylinder configuration places the cylinders in a single row either completely vertical or slanted. Due to this arrangement, an inline cylinder configuration makes the engine longer and, although it works well in four cylinder engines, performace suffers in larger engines due to the difficulty in evenly distributing the air-fuel mixture over the length of the engine.

Once the engine is running, the alternator provides electrical current to recharge the battery and power the electrical system. The alternator is driven by the engine's crankshaft and produces alternating current (AC) which is then fed through a rectifier bridge to convert it to the direct current (DC) required by the electrical system. A voltage regulator controls the output of the alternator to maintain a consistent voltage (approx. 14.5 volts) in the electrical system regardless of load.

An overcooled engine is less efficient. During the power stroke, combustion heat pushes down the piston. If too much of this heat is lost to the cooling system, the fuel might not combust completely and contaminate the engine's lubricating oil diminishing its lubricating ability. Incomplete combustion of fuel also negatively affects the engine's fuel efficiency and power output.