Fuel System Problems:
* Fuel Pump Failure: A failing fuel pump might not deliver enough fuel at higher RPMs or under load, causing the engine to starve for fuel and die.
* Clogged Fuel Filter: A clogged filter restricts fuel flow, leading to similar symptoms as a failing fuel pump.
* Fuel Pressure Regulator Issues: A malfunctioning regulator can cause inconsistent fuel pressure, leading to erratic engine behavior and stalling.
* Bad Fuel Injectors: Clogged or faulty injectors can prevent sufficient fuel delivery to the cylinders.
Ignition System Problems:
* Distributor Issues (if equipped): Worn distributor cap, rotor, or points (if not electronic ignition) can cause intermittent spark failure.
* Ignition Coil Failure: A failing coil won't produce the necessary high voltage for consistent spark.
* Worn Ignition Wires: Damaged or corroded wires can lead to poor spark delivery.
* Crankshaft Position Sensor (CKP) or Cam Position Sensor (CMP): These sensors tell the computer the engine's rotational position. A failing sensor will cause the computer to shut off the fuel and/or spark.
Electrical System Problems:
* Alternator Failure: If the alternator isn't charging the battery, the engine might shut off once the battery is depleted. This is often accompanied by dimming lights.
* Battery Problems: A weak or failing battery can cause the engine to stall, especially under load.
* Loose or Corroded Connections: Poor connections in the electrical system can disrupt power delivery.
Other Potential Causes:
* Vacuum Leaks: Leaks in the vacuum system can disrupt engine timing or other vital functions.
* Throttle Position Sensor (TPS) Problems: A faulty TPS can cause the computer to misinterpret engine load and shut down.
* Engine Temperature Sensor: A malfunctioning sensor can cause the computer to take incorrect actions, including shutting down the engine.
* Computer Issues (ECM/PCM): While less common, a failing engine control module can cause unpredictable engine behavior.
* Overheating: An overheated engine can trigger safety shutdowns. Check your coolant level and look for signs of leaks.
Troubleshooting Steps:
It's crucial to diagnose the problem systematically. Start with the easier checks:
1. Check the obvious: Battery voltage, coolant level, and look for any obvious leaks.
2. Listen for unusual noises: Any unusual sounds from the fuel pump or other engine components could indicate a problem.
3. Check the fuel: Make sure you have enough fuel and that it isn't contaminated.
4. Inspect wiring and connections: Look for loose, corroded, or damaged wires and connectors.
If you're not comfortable working on your car yourself, take it to a qualified mechanic for diagnosis and repair. They have the tools and expertise to pinpoint the exact cause of the problem efficiently and safely. Providing them with as much detail as possible about when the problem occurs (e.g., under load, after driving a certain distance, during acceleration) will greatly assist them in their diagnosis.
