Why does the car make abnormal noise when starting but not after starting?
3 Answers
Because there is a malfunction in the engine compartment, the torque vibration of the engine is significant when the vehicle starts. The following are relevant introductions about cars: 1. Precautions: Develop the habit of fastening the seat belt when getting in the car. According to Article 51 of the "Road Traffic Safety Law of the People's Republic of China": When a motor vehicle is in motion, the driver and passengers shall use seat belts as required, and motorcycle drivers and passengers shall wear safety helmets as required. 2. Maintenance tips: Clean, tighten, inspect, and replenish. The air contains a large amount of dust, sand, and acidic substances, which are not only easily adhered to by leaking fuel but also tend to form a hard insulation layer when baked at high temperatures, hence maintenance is required.
I experienced a similar issue when driving that old manual transmission car. Every time I released the clutch to start moving, the chassis would make a creaking sound, like an old wooden door opening and closing. This kind of noise is a clear sign of worn-out bushings or loss of elasticity in the suspension system's rubber components, as the body undergoes slight torsional deformation during startup. Just ask your mechanic to poke the control arm bushings and stabilizer links with a pry bar - cracked rubber will squeal instantly under pressure. Don't underestimate these few-dollar bushings; when they're completely worn out, you'll feel looseness when cornering. If the engine mounts are aged, you'll also hear brief metal clunking sounds during startup - these need immediate replacement. Nowadays, the first thing I do at the repair shop is have them remove the wheels to inspect all rubber components.
A neighbor asked me the same question a couple of days ago. His city SUV made a rattling sound from the tire area every time it started moving. I told him to check under the fender liner, and sure enough, there were small stones stuck there, with several nail-head-sized gravel pieces embedded in the tire treads. Especially on newly paved asphalt roads, it's easy to pick up asphalt particles that get lodged in the brake disc shields, causing a singing noise during initial movement. Another possibility is fatigued brake pad springs, which can cause a scraping vibration when releasing the brakes. I suggested first using a water spray to clean the inner wheel arches. If the noise persists, remove the wheels to inspect the brake pad retaining springs. Many unusual noises don't require engine disassembly—often, it's just small objects causing trouble.
