* Crankshaft Position Sensor (CKP): This sensor tells the engine's computer where the crankshaft is positioned. A faulty CKP sensor will prevent the engine from receiving the signals it needs to stay running. This is a very common cause of this type of problem.
* Cam Position Sensor (CMP): Similar to the CKP sensor, but for the camshaft. A faulty CMP can also lead to the engine shutting down shortly after starting.
* Fuel Pump: The fuel pump might be weak, failing to deliver enough fuel pressure to sustain the engine's operation. It could be the pump itself, the fuel pump relay, or a problem in the fuel pump wiring. Listen closely as you crank the car; you should hear the fuel pump whir for a few seconds before cranking. A lack of whirring is a strong indicator.
* Fuel Filter: A clogged fuel filter could restrict fuel flow, causing the engine to stall.
* Throttle Position Sensor (TPS): A malfunctioning TPS might provide incorrect information to the engine control unit (ECU), leading to the engine shutting down.
* Mass Airflow Sensor (MAF): A dirty or faulty MAF sensor can provide inaccurate air readings, causing the engine to misfire and shut down.
* Ignition System Problems: This could include faulty spark plugs, wires, ignition coil, or the ignition control module. While less likely to cause a shutdown *immediately* after starting, weak components might be able to sustain the initial firing but then fail under load.
* Security System: Though less common, a problem with the vehicle's anti-theft system could prevent the engine from running continuously.
Troubleshooting Steps:
1. Check for Diagnostic Trouble Codes (DTCs): Use an OBD-II scanner to read any error codes stored in the car's computer. This is the *first* thing you should do. The codes will often point directly to the failing component.
2. Check Fuel Pressure: This requires a fuel pressure gauge and some mechanical knowledge. Low fuel pressure confirms a fuel system problem.
3. Inspect Fuel Pump Relay: A simple visual inspection for damage or corrosion can rule this out.
4. Check the Crankshaft and Camshaft Position Sensors: These sensors can often be tested with a multimeter, although it's often easier to simply replace them if a DTC points to a problem.
5. Check Spark: While this is more involved, verifying that spark is consistently reaching all cylinders will rule out ignition problems.
It's crucial to have this diagnosed and repaired by a qualified mechanic if you lack the experience to perform these checks yourself. Attempting some repairs without proper knowledge could cause further damage. The intermittent nature of the problem makes accurate diagnosis challenging, so professional help is highly recommended.
