An engine requires air, fuel, and spark to function properly, and when one or more of these components fail, the engine will stall. To confirm what is causing the car's engine to stall, the vehicle's computer will need to be plug into a diagnostics machine.
When the ignition is turned on in a vehicle, spark travels to the starter, battery and fuel pump. The flywheel spins and air is simultaneously sucked into the combustion chamber where small explosions occur. These small explosions cause an engine's crankshaft to spin and create power. When one or more of these components fail, the engine will be unable to maintain power and will shut off.
There are a few common causes of engine failure:
- Lack of spark - an alternator provides continual power to the battery of a vehicle. If the unit or the battery fails the car will be unable to run at its optimal setting. This will result is a weak idle that will eventually stall the engine
- Fuel pressure loss - when there is a lost of fuel pressure, while the engine is running, the car will turn off. Loss of fuel pressure results from worn fuel lines, fuel pumps or fuel injectors
- Air leak - the most common cause of intermediate stalling issues deal with an air leak, commonly referred to as a vacuum leak. A vacuum leak results from a torn or damaged hose, gasket or o-ring