Fuel System Problems:
* Clogged Fuel Filter: Restricts fuel flow, leading to the engine sputtering and dying.
* Low Fuel Pressure: A failing fuel pump or regulator can't deliver enough fuel to maintain running.
* Dirty Fuel Injectors: Clogged injectors prevent proper fuel delivery.
* Bad Fuel Pump Relay: The relay might not be sending power to the fuel pump.
Ignition System Problems:
* Crankshaft Position Sensor (CKP): This sensor tells the engine's computer where the crankshaft is. A faulty one can cause the engine to stall after starting.
* Cam Position Sensor (CMP): Similar to the CKP, but for the camshaft.
* Ignition Coil: Supplies the spark to the spark plugs. A faulty coil can lead to misfires and stalling.
* Spark Plugs/Wires: Worn or damaged spark plugs or wires can prevent proper ignition.
* Distributor (if equipped): Issues with the distributor cap, rotor, or internal components can disrupt the spark delivery.
Other Potential Problems:
* Mass Airflow Sensor (MAF): Measures the amount of air entering the engine. A faulty sensor can cause a lean fuel mixture, leading to stalling.
* Throttle Position Sensor (TPS): Tells the computer the throttle position. A faulty sensor can provide incorrect information, leading to stalling.
* Idle Air Control Valve (IAC): Controls the idle speed. A faulty IAC can cause the engine to stall, especially when idling.
* Vacuum Leaks: Leaks in the vacuum lines can disrupt engine operation and cause stalling.
* Battery/Alternator: A weak battery or failing alternator can cause the engine to stall if it can't provide enough power.
* Computer Issues (PCM): Though less common, a faulty PCM can cause various issues, including stalling.
Troubleshooting Steps (in general order, some require professional tools):
1. Check the obvious: Ensure you have enough fuel. Check the battery terminals for corrosion and tightness.
2. Listen for unusual noises: A ticking, clicking, or whining sound might indicate a specific problem area.
3. Check engine codes: Use an OBD-II scanner to retrieve any diagnostic trouble codes (DTCs) stored in the PCM. These codes will point you towards the most likely culprit.
4. Visual inspection: Look for obvious signs of damage, leaks, or loose connections.
5. Test fuel pressure: A fuel pressure gauge is needed for this.
6. Test sensors (MAF, TPS, CKP, CMP): Requires a multimeter and specific knowledge of testing procedures.
Important Note: Without a proper diagnosis using a scan tool and possibly further testing, replacing parts randomly is expensive and may not solve the problem. It's highly recommended to take the vehicle to a qualified mechanic for diagnosis and repair. They have the tools and expertise to identify the root cause efficiently.
