What are the reasons for a car not starting and producing abnormal noises?

[VanAvery]

There are several reasons why a car may not start and produce abnormal noises: 1. If the car has been parked for a long time, the engine oil in the internal oil passages may flow back into the oil pan (some oil passages have pressure-retaining valves). Additionally, as the temperature gradually drops, the low-temperature flow performance of the oil deteriorates. When the engine is cold-started, the oil cannot be delivered to the designated lubrication points in time, requiring a certain amount of time for pumping, which results in a "clicking" abnormal noise. 2. Apart from engine-related factors, a component on the engine can also automatically simulate a "clicking" sound. This component is the carbon canister solenoid valve. Its function is to open when the engine starts (or during rapid acceleration), allowing the gasoline vapor adsorbed in the carbon canister to be drawn into the intake manifold under vacuum and then into the cylinders for combustion. This process aims to reduce gasoline pollution to the environment and also lowers fuel consumption.

[StAlan]

I've encountered many car owners facing this issue where the car won't start and makes strange noises, most commonly caused by insufficient battery power. When the battery is old or has been left unused for a long time without charge, the starter motor struggles to turn, producing a harsh clicking or grinding sound, resembling gears spinning freely. Other causes include damage to the starter motor itself, such as worn internal carbon brushes leading to unstable rotation, or burnt relay contacts creating noise when powered. It could also be due to fuel pump or ignition system failures, resulting in startup failure and noise. In such cases, avoid repeatedly attempting to start the car forcefully, as this can worsen the damage. It's advisable to first check the battery's condition and measure if the voltage meets the standard—consider replacing it if it's below 12V. If that doesn't solve the issue, inspect for loose connection wires. Lastly, promptly visit a professional repair shop for a comprehensive diagnosis to avoid increasing repair costs. Safety comes first; ensure the vehicle is reliable before hitting the road.

[LeGage]

Last time my car had the same issue - no response when starting in the morning, accompanied by a grating noise. It was so frustrating. I recalled similar winter incidents before, which turned out to be loose battery terminals causing poor contact. Tightening them slightly solved it. But now with this obvious abnormal noise, I suspect the starter motor is acting up - maybe gears are jammed or internal damage; or possibly unstable alternator voltage causing strange sounds. Ordinary car owners like me would first check the battery's lifespan to see if replacement is needed. Also, don't listen to those suggesting hitting the motor with a hammer - that's completely unreliable and might damage more components. Just visit a roadside repair shop - they can diagnose the cause in minutes. Don't waste time. Remember, minor issues escalating into major troubles happens all too often.

[VanLucas]

The car won't start and makes abnormal noises. The key is to identify the type of noise to determine the cause. A clicking sound is likely a relay switch issue, indicating current flow but the motor not working; continuous rattling may indicate starter gear wear or slippage. If it's a heavy metal grinding sound, there could be serious hidden dangers, such as internal engine bearing damage or chain misalignment. These can prevent normal ignition, leading to complete lockup. Once this occurs, don't repeatedly attempt to start; stop immediately and inspect to avoid further damage. Abnormal noises are warning signals, indicating components are under abnormal stress. Visit a repair shop promptly to diagnose and fix the root cause with diagnostic equipment. The core of safe driving is taking quick action when problems are detected.

[LeJoel]

When your car won't start and makes strange noises, it's no small matter. This usually indicates core component issues, such as starter system failure or mechanical faults; persistent neglect may turn the noise into louder sounds, even leading to engine failure. Imagine how dangerous this could be in traffic—your vehicle completely breaking down not only disrupts traffic flow but may also cause accidents. Common causes include: aging batteries or insufficient voltage triggering sounds; or the starter motor getting stuck and noisy after prolonged wear. For maintenance, regularly checking these components' lifespan can reduce risks—it's recommended to visit the garage every six months. From a safety perspective, don't wait until complete failure occurs; if it happens, pull over and call for towing services. Prevention is better than repair.

[VanClaire]

In my daily handling of such issues, I've found that strange noises coupled with startup failure require some simple self-checks first. For example, use a multimeter to test the battery voltage: if it's below 10V, insufficient charge is likely the main culprit; the strange noise is often the starter motor protesting. Next, check if the cable connections are corroded or loose, and try gently tightening them with a wrench. If the car starts but the sound is abnormal, it could be fuel pump noise or a faulty ignition coil affecting operation. Don't rush to replace parts blindly—first, note when the noise occurs: during startup or continuously? This helps when describing the issue to a technician. These steps might sometimes fix the problem yourself; otherwise, take it to a professional shop to check mechanical bearings or system logic. Ensure safety when working on it, and don't overdo it—just send it for repair if needed.