What are the causes of abnormal noises in a car?
2 Answers
There are several reasons that may cause abnormal noises in a car: 1. Long service life of the engine: Some cars have engines that have been used for too long, and high idle speed during each startup may cause abnormal noises. 2. The engine oil used during maintenance is also a contributing factor: Expensive engine oil is not necessarily the best; it must be suitable for your car. Unsuitable engine oil can produce certain abnormal noises. 3. Belt wear: Cars with long service lives may need belt replacements, and worn belts can also produce such noises.
That time when I drove my old Jetta over speed bumps, the chassis kept making a 'clunking' noise. After struggling for a while, I finally found out it was due to cracked bushings on the lower control arm. This kind of abnormal noise is particularly sensitive to road conditions, being most noticeable when going over potholes or bumps. Another time, I heard a sharp metallic sound while braking—turned out the brake pads had worn down to the warning indicator. Ignoring it would have damaged the brake disc. A 'creaking' noise when turning might indicate an issue with the steering gear, while a 'ticking' sound in the engine bay at idle is often due to an aging belt. I recommend taking an experienced mechanic for a test drive; using a stethoscope pressed against areas like the strut tower or wheel bearings is the most accurate way to locate the source of the noise. For chassis components like ball joints on control arms, any play can cause loose and abnormal noises, which require inspection on a lift to diagnose properly.