What are the reasons for a car suddenly stalling during normal operation and failing to restart?
3 Answers
Car suddenly stalling during normal operation and failing to restart can be caused by: 1. Short circuit in the positive terminal of the power system to ground; 2. Short circuit in the starter control circuit; 3. Fault in the starter itself; 4. No control voltage in the starter signal line; 5. Internal fault in psf1. The starter converts the electrical energy from the battery into mechanical energy, driving the engine flywheel to rotate and enabling the engine to start. The cylindrical component on the starter is the solenoid, which functions to push the gear forward, engaging the starter gear with the engine's flywheel. The lower cylindrical component is the starter motor, responsible for providing the torque needed to start the engine.
I've been driving for over a decade and encountered this issue several times. It's most likely a fuel system problem. Sudden stalling during normal operation with failure to restart usually indicates a fuel supply interruption – possibly a failed fuel pump that can't deliver fuel. A clogged fuel filter or empty tank (with inaccurate fuel gauge causing you to forget refueling) can also cause this. Last time my car stalled on the highway, the starter cranked but couldn't ignite – inspection revealed a silent pump needing replacement. Insufficient fuel pressure causes engine shutdown. I recommend first listening for pump operation during diagnosis to avoid dangerous roadside breakdowns. Regular maintenance with fuel system cleaning can prevent this. Another possibility is poor electrical connection in fuel delivery wiring that burns out under high heat – safest approach is calling for tow truck service immediately.
From a mechanic's perspective, this situation is often caused by ignition system failure. The engine stalls while driving and fails to start, which could be due to insufficient spark plug ignition or a faulty coil preventing the spark plug from igniting the fuel. A misreporting crankshaft position sensor may cause the ECU to mistakenly cut off fuel and electricity supply. During inspection, if you hear the starter engaging but the engine doesn't fire, it's mostly an ignition issue. I usually check the spark plug condition and replacement interval, as sensors are prone to dust contamination and frequent failures. Additionally, unstable voltage from alternator charging issues or depleted battery can also cause starting failure. I recommend regular maintenance of ignition components and upgrading when necessary.
