Fuel System:
* Fuel pump failure: The fuel pump might be failing to deliver fuel to the engine. This is a common cause of sudden stalling.
* Clogged fuel filter: A clogged filter restricts fuel flow, leading to engine starvation and stalling.
* Fuel pressure regulator problems: A malfunctioning regulator could deliver incorrect fuel pressure.
* Bad fuel injectors: Clogged or malfunctioning injectors can prevent proper fuel delivery.
Ignition System:
* Crankshaft Position Sensor (CKP) failure: This sensor tells the engine's computer where the crankshaft is, and a failure will prevent the engine from running.
* Cam Position Sensor (CMP) failure: Similar to the CKP sensor, a faulty CMP sensor prevents proper engine timing.
* Ignition coil failure: A failing coil can prevent a cylinder or multiple cylinders from firing.
* Spark plugs/wires: Worn-out spark plugs or damaged wires can lead to misfires and stalling.
* Ignition switch issues: While less common, a faulty ignition switch can interrupt the electrical flow needed for the engine to run.
Electrical System:
* Alternator failure: If the alternator fails, the battery will eventually drain, causing the engine to stop.
* Battery issues: A dead or weak battery can prevent the engine from starting or stalling while running.
* Loose or corroded battery terminals: Poor connections can interrupt the electrical flow.
* Faulty PCM (Powertrain Control Module): The PCM controls many engine functions, and a failure can cause a variety of problems, including stalling. This is a more serious and expensive problem.
Other Potential Causes:
* Transmission problems: While less likely to cause an immediate stop, serious transmission issues could lead to a sudden loss of power and stalling.
* Vacuum leaks: Leaks in the vacuum system can disrupt engine performance and cause stalling.
* Throttle position sensor (TPS) failure: An inaccurate reading from the TPS can cause the engine to stall.
* Overheating: An overheated engine can shut itself down to prevent damage. Check your coolant level.
Troubleshooting Steps (Do NOT attempt major repairs yourself unless you are experienced):
1. Check the obvious: Battery terminals, coolant level, and obvious signs of leaks.
2. Listen for unusual noises: Unusual sounds coming from the engine might provide clues.
3. Have it towed to a mechanic: Given the sudden stop while driving, attempting to diagnose this yourself could be dangerous. A professional mechanic has the tools and experience to diagnose the problem accurately and safely.
This is not an exhaustive list, and the precise cause can only be determined with a proper diagnosis by a qualified mechanic. Do not drive the car until it's been checked, as continuing to drive it with a serious issue could lead to further damage or create a safety hazard.
