What's the reason for the engine not starting?

[VanNaomi]

The engine may fail to start for many reasons. Possible causes include an empty fuel tank, a faulty fuel pump, incorrect timing, malfunctioning crankshaft or camshaft position sensors, issues with the anti-theft system, or starter motor failure. It is recommended to have it inspected and repaired at a 4S shop. Below are methods for diagnosing engine abnormalities: 1. Check the battery: Under normal engine conditions, faults in the starter or battery can make the engine difficult to start. In such cases, first assess the condition of the starter and battery to roughly identify the faulty component. It's essential to determine whether the engine's failure to start is due to insufficient battery charge. 2. Inspect the starting system: When the engine fails to start, the first step is to examine the electrical circuits of the engine's starting system. The starting system's circuits typically include the battery, starter motor, and connecting cables. Additionally, the ignition switch, starter relay or solenoid, and the vehicle's anti-theft system are also crucial components of the starting system. 3. Diagnose the fuel system: The diagnosis of the fuel system can be divided into two parts: the fuel supply system and the fuel injector circuit system. The fuel supply system can be checked by measuring fuel flow and pressure. The best method for measuring fuel flow is to test the fuel supply line under load.

[JourneyLynn]

Last time my car wouldn't start was really frustrating. Turned out the battery was dead - when trying to start it, there was only a clicking sound. I had to call roadside assistance for a jump start, and the mechanic said car batteries typically last 3-5 years, mine had been used for 6 years and was long overdue for replacement. Low fuel can also cause starting issues - I remember once driving with the fuel warning light on until the car completely stalled. Other potential culprits include starter motor failure or the anti-theft system locking the key, all needing systematic checks. Now during every maintenance service I have the mechanic test the battery voltage, and keeping a portable jump starter in the car gives me peace of mind. Actually, extremely cold weather also affects starting, especially for older vehicles that need pre-warming.

[ODelilah]

From a professional perspective, engine failure to start involves multiple systems. Ignition system malfunctions are common, such as spark plug carbon buildup or aging ignition coils preventing proper ignition. Fuel supply issues should not be overlooked either, as a burned-out fuel pump or clogged fuel injector can interrupt fuel delivery. Electrical problems are more complex - insufficient battery charge, starter relay failure, or blown fuses may all cause ignition failure. Although rare, ECU control unit faults require professional diagnosis. When encountering this situation, it's recommended to first check battery voltage and fuses, then test fuel pressure and ignition signals. Avoid blindly disassembling components - using a diagnostic tool to read fault codes can achieve twice the result with half the effort.

[WalterMarie]

Don't panic if your car won't start as a beginner, I'll teach you a simple three-step check. First, check the dashboard: when turning the key to the ON position, see if the warning lights come on. If they don't light up at all, it's likely a battery issue. Then, listen for sounds: a clicking noise without the engine turning over might indicate a weak battery, while no sound at all could mean a faulty starter. Finally, check the fuel level—don't laugh, some people really forget to refuel. For automatic transmissions, ensure it's in P (Park); for manual transmissions, press the clutch. If all these are normal, it might be a blown fuse—check the manual to locate the starting system fuse. If all else fails, don't force it; calling a tow truck is more practical.