The electrical current needed to initiate the combustion process in an internal combustion engine varies depending on several factors. These factors include engine size, ambient temperature, and the condition of the battery and starter motor. A typical passenger vehicle may require a substantial surge of electrical energy to turn the engine over sufficiently for ignition.
Adequate current delivery is crucial for reliable vehicle operation. Insufficient amperage can lead to starting failure, particularly in cold weather when engine oil viscosity increases and greater force is required to rotate the crankshaft. Historically, understanding the current demands of a starter motor has been a fundamental aspect of automotive electrical system design, influencing the selection of battery capacity and wiring gauge.