What causes the clicking sound when starting a car after it has been parked for several days?
4 Answers
Because of ignition delay, unburned gasoline is just discharged into the exhaust pipe when the spark plug ignites, and the sound is produced when the atomized gasoline is ignited in the exhaust pipe. This is mainly due to the vehicle being parked for too long, causing the battery to drain. Starting the car after 7 or 8 attempts is considered a good situation. Generally, if the vehicle remains unused for an extended period, it is best to charge the battery every three days and let the engine idle for about 10 minutes. If the car has aftermarket navigation systems or similar large electrical accessories, the power consumption will be even more severe. Below is additional information: 1. The abnormal sound only occurs during idling or low-speed operation. Possible causes include: excessive clearance between the piston and cylinder wall; overly tight piston pin or connecting rod bearing assembly; excessive clearance between the tappet and its guide hole; wear on the camshaft profile; sometimes, a loose starter pulley causing noise (more noticeable during speed changes). 2. When maintaining a certain speed, the sound becomes chaotic, and brief noises occur during rapid deceleration. Possible causes include: cracked camshaft timing gear or loose fixing nut; broken crankshaft; loose piston pin bushing; excessive axial clearance of the camshaft or loose bushing. 3. The abnormal sound appears during rapid acceleration and persists during high-speed operation. Possible causes include: loose connecting rod bearing, melted or mismatched bearing shell; loose crankshaft bearing or melted bearing shell; broken piston pin; broken crankshaft.
My car has a similar issue. After being parked for a few days, there's a clicking sound when starting to move, which is usually caused by rust on the brake discs. After parking in humid weather, the surface of the brake discs rusts and sticks to the brake pads. When you release the brake to start moving, the stuck part gets torn apart, making that sound. It's no big deal—the noise disappears after driving a short distance. However, if ignored, long-term sticking could accelerate wear or cause other components to jam. I recommend parking in a dry place, not pulling the handbrake too tight, and using the P gear instead. Occasionally check for debris stuck under the wheels. If the sound is very loud or persists, it's best to have a professional shop check if the brake system is aging. Remember to drive the car regularly to prevent similar issues.
I just bought the car and it's like this. Every time I start it after parking for a few days, there's always a clicking sound, which scares me. It turns out the brake discs are rusty, and rain or moisture causes them to stick to the brake pads. When I release the brakes, they separate and make that noise. This isn't a major issue; occasionally it's fine. But if it happens every time or the sound is particularly loud, it could be due to a stuck brake caliper or insufficient lubrication of the half-shaft. My friend said turning on the air conditioning to dehumidify can also reduce the impact of humidity. It's best to lightly press the brakes before starting to check for any abnormalities. To prevent accidents, I should quickly go see a mechanic.
A loud clicking noise when starting a car that has been parked for a long time is mostly caused by rusted and stuck brake discs. When there is a lot of rain, the surface rusts, and the noise occurs when the brakes are released and the rust is torn apart. This often disappears after simple treatment, but if the sound persists, attention should be paid to brake system failures such as caliper sticking. It is recommended to go to a repair shop for a comprehensive inspection to avoid long-term wear and tear.
