What Causes the Buzzing Noise When Driving at High Speed?
1 Answers
Engine Knock: This is a sound similar to metal knocking, also known as piston slap. The causes can be divided into three types: substandard fuel, such as using poor-quality fuel or fuel with an octane rating that is too low; incorrect engine timing control, such as an excessively advanced ignition timing, which requires readjusting the timing; or excessive carbon buildup inside the engine. You can first try carbon cleaning through no-disassembly cleaning or driving at high speed to test the cleaning effect. Otherwise, the engine must be disassembled to clean the carbon deposits. Severe cases often come with significant oil burning issues. Valve Noise: After starting the engine, a "ticking" sound is heard. This is the sound of the valves, especially noticeable when the engine is cold. This happens because the oil pressure hasn't built up yet, and the valves aren't properly lubricated. It usually goes away after a short while. If your car has been parked for a long time, this situation may occur. If the sound persists, it could indicate excessive valve clearance or oil leakage at the camshaft, requiring adjustment of the valve clearance or replacement of the relevant oil seals. Engine "Backfire" Issue: When decelerating and lifting off the throttle, a "popping" sound may occur, which could be an engine "backfire" issue, commonly referred to as engine "backfiring." Excessive carbon buildup on the valves or incorrect valve timing can cause this noise. Cleaning the valve carbon deposits or adjusting the valve timing may resolve the issue.
