Fuel System Problems:
* Fuel pump failure: The pump might be failing to deliver enough fuel to the engine.
* Clogged fuel filter: A dirty filter restricts fuel flow.
* Low fuel: Obvious, but surprisingly common.
* Fuel injectors malfunctioning: Injectors might be clogged, leaking, or failing to spray fuel properly.
* Fuel pressure regulator problems: This regulates the fuel pressure; a malfunction can lead to inconsistent fuel delivery.
Ignition System Problems:
* Distributor cap and rotor issues (older vehicles): Worn or damaged components can disrupt the spark delivery.
* Ignition coil failure: This component provides the high voltage for sparking.
* Spark plugs malfunctioning: Worn, fouled, or damaged spark plugs prevent proper combustion.
* Ignition switch problems: The switch might be failing to provide power to the ignition system.
* Crankshaft position sensor failure: This sensor tells the computer the engine's rotational position, crucial for ignition timing.
Engine Problems:
* Mass airflow sensor (MAF) failure: This sensor measures the amount of air entering the engine; a faulty sensor leads to incorrect fuel mixture.
* Throttle position sensor (TPS) failure: This sensor tells the computer the throttle position; a faulty sensor leads to poor fuel delivery.
* Vacuum leaks: Leaks in the vacuum system can disrupt the engine's operation.
* Overheating: An overheated engine can cause stalling.
* Timing belt/chain issues: A broken or slipping timing belt/chain causes catastrophic engine damage and stalling.
* Low compression: Worn piston rings or valve problems can reduce compression, preventing proper combustion.
Transmission Problems (Automatic):
* Transmission failure: A major transmission problem can cause the car to stall. This is more likely to manifest as a loss of power rather than a sudden stall, however.
Other Potential Causes:
* Alternator failure: While the car might run for a while on battery power, a failing alternator will eventually cause a stall.
* Battery problems: A weak or dying battery can lead to stalling, especially in cold weather or after using a lot of electrical accessories.
* Computer issues (ECU): The Engine Control Unit can malfunction, causing various issues including stalling.
* Brake booster vacuum leak: A leak in the brake booster vacuum line can cause a stall due to the engine needing to supply vacuum to the brakes.
Troubleshooting:
If your car stalls, it's crucial to get it checked by a mechanic. Trying to diagnose the problem yourself without the proper knowledge and tools can be dangerous and may even worsen the issue. However, observing *when* the car stalls (e.g., at idle, under load, after a specific action) can provide valuable clues for the mechanic.
