A stall is the slowing or stopping of a process and in the case of an

engine An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ...

refers to a sudden stopping of the engine turning, usually brought about accidentally. It is commonly applied to the phenomenon whereby an engine abruptly ceases operating and stops turning. It might be due to not getting enough air,

energy In physics, energy (from Ancient Greek: ἐνέργεια, ''enérgeia'', “activity”) is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of ...

fuel A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy b ...

, or electric spark, fuel starvation, a mechanical failure, or in response to a sudden increase in engine load. This increase in engine load is common in vehicles with a

manual transmission A manual transmission (MT), also known as manual gearbox, standard transmission (in Canada, the United Kingdom, and the United States), or stick shift (in the United States), is a multi-speed motor vehicle transmission (mechanics), transmission ...

when the clutch is released too suddenly. The ways in which a car can stall are usually down to the driver, especially with a manual transmission. For instance, if a driver takes their foot off the clutch too quickly while stationary then the car will stall; taking the foot off the clutch slowly will stop this from happening. Stalling also happens when the driver forgets to depress the clutch and/or change to neutral while coming to a stop. Stalling can be dangerous, especially in heavy traffic. A car fitted with an

automatic transmission An automatic transmission (sometimes abbreviated to auto or AT) is a multi-speed transmission used in internal combustion engine-based motor vehicles that does not require any input from the driver to change forward gears under normal driving ...

could also have its engine stalled when the vehicle is travelling in the opposite direction to the selected gear. For example, if the selector is in the 'D' position and the car is moving backwards, (on a steep enough hill to overcome the torque from the torque converter) the engine will stall, due to the fact that the engine is forced to turn in the opposite direction to what it is actually doing. This is because, hypothetically, if the car is rolling backward fast enough, the force from the rotating wheels will be transmitted backward through the transmission and act as a sudden load on the engine. Digital electronics fuel injection and ECU ignition systems have greatly reduced stalling in modern engines.

References

Mechanics Machines Driving techniques Automobile engines Distress signals {{Mech-engineering-stub

See also

References