What Causes the Abnormal Noise When the Engine Just Starts?

[GiselleAnn]

It is due to a fault in the carbon brushes inside the starter motor. Below is an introduction to the causes of abnormal noise when the engine just starts: Causes of abnormal noise: Over time, the engine belt may age and slip, producing a squeaking sound; loose engine mount bolts can lead to improper engine support installation. If the engine mount bolts are loose, you can locate and tighten the specific screws yourself. If the noise is caused by a loose or aged belt, replacing it with a new one can solve the issue. If the carbon brushes inside the motor are faulty, it is necessary to seek professional assistance at a 4S shop, as dismantling the engine by yourself is not recommended. Maintenance awareness: With high mileage and prolonged use, the engine valves and hydraulics will experience a certain degree of wear. Excessive wear can lead to abnormal noises. To address this issue, the cylinder head needs to be disassembled to replace these components. A way to mitigate this problem is by regularly changing the oil. Avoid overusing the oil, as it can degrade the lubrication effect, thereby accelerating the wear of valves and hydraulics. During a cold engine start, due to the viscosity and poor fluidity of the oil, operational noise may occur in the short term, and slight noises may be heard when moving parts come into contact.

[PatrickMarie]

I've been driving for over a decade and often encounter strange noises when starting the engine. The most common issue is related to engine oil, such as insufficient oil level or oil that's too thick. During cold morning starts, inadequate lubrication of components can cause friction or tapping sounds. Alternatively, it could be a loose or worn fan belt, producing obvious squeaking noises. A stuck starter motor gear might also generate noise during the initial start. Another possibility is a loose timing chain, resulting in metallic knocking sounds. I recommend car owners first check the oil dipstick to ensure proper oil level; if the noise persists after changing to fresh oil, have the belts and starting components inspected at a repair shop. Don't ignore these sounds - minor noises often indicate underlying issues that could potentially damage the engine if left unaddressed for long periods.

[CarlosDella]

As a young car enthusiast, I did some research after noticing abnormal engine startup noises. The causes vary: piston slap occurs when oil pressure hasn't built up, causing cylinder friction sounds at startup; aged hydraulic lifters produce ticking noises; loose belt systems squeal. Additionally, thick cold-weather oil flows poorly, making noises more frequent. Solutions include warming up the car for 1-2 minutes before driving to alleviate issues, and using proper oil with chain inspections during maintenance. Never guess blindly - timely professional diagnosis is crucial for safety.

[LaVera]

From my experience, abnormal noises during startup are mostly caused by substandard engine oil. For instance, if the oil is too old or the viscosity is inappropriate, insufficient lubrication during cold starts can lead to clicking sounds. A faulty or worn belt tensioner can also produce a screeching noise. For a simple check, first inspect the oil level yourself. If the noise persists after ensuring the oil level is normal, it might involve loose components, such as the fan or starter. Get it checked as soon as possible to prevent damage.