Fuel System Problems (Most Likely):
* Clogged Fuel Filter: This is a common and relatively inexpensive fix. A clogged filter restricts fuel flow, causing the engine to stall after starting.
* Weak Fuel Pump: The pump might be failing to provide sufficient pressure to deliver fuel to the injectors. It may work for a few seconds upon initial cranking then fail. Listen closely for the pump's whirring sound when you turn the key to the "on" position (before cranking). If you don't hear it, or it's weak, it's a suspect.
* Fuel Pump Relay: The relay acts as a switch for the fuel pump. A faulty relay prevents power from reaching the pump.
* Clogged Fuel Injector(s): A clogged injector prevents fuel from reaching the combustion chamber. This is less likely to cause an immediate stall after starting, but it's possible one or more are completely blocked.
* Low Fuel Level: While seemingly obvious, make sure you actually have enough fuel. The fuel level sensor can sometimes be faulty, too.
* Fuel Pressure Regulator: This regulates the pressure in the fuel rail. A faulty regulator can cause erratic fuel pressure, leading to stalling.
Other Possibilities:
* Crankshaft Position Sensor (CKP Sensor): This sensor tells the engine's computer where the crankshaft is positioned. A faulty CKP sensor can prevent the engine from running consistently, even if it starts briefly.
* Mass Airflow Sensor (MAF Sensor): This sensor measures the amount of air entering the engine. A faulty MAF sensor can cause the engine to run lean (lack of fuel relative to air), resulting in stalling.
* Ignition System Problems: While less likely to cause an immediate stall after starting, issues like a bad ignition coil or distributor cap/rotor could contribute. However, you'd likely have other symptoms like misfires.
* Throttle Position Sensor (TPS): A faulty TPS won't allow the engine computer to accurately control fuel delivery.
* Computer Issues (PCM): Though less common, a failing engine control module can cause erratic behavior, including stalling.
Troubleshooting Steps:
1. Check the fuel level: This is the easiest and first step.
2. Listen for the fuel pump: Turn the ignition key to the "on" position (but don't crank the engine). You should hear a brief whirring sound from the fuel pump. If not, or if it's weak, it points towards a fuel pump or relay problem.
3. Check fuel pressure: This requires a fuel pressure gauge and some mechanical knowledge. It directly assesses the fuel system's pressure.
4. Inspect the fuel filter: It's relatively easy to access and check visually for damage or clogging.
5. Check for error codes: Your car likely has an OBD-I diagnostic system (check under the hood or your owner's manual for a connector). Using a code reader might provide valuable insights.
Important Note: Diagnosing car problems requires some mechanical knowledge and potentially specialized tools. If you're not comfortable working on your car, it's best to take it to a qualified mechanic. Attempting repairs without proper knowledge could worsen the problem. Providing additional details like any warning lights, sounds (other than the fuel pump), or other symptoms will help narrow down the possible causes.
