What is the solution for engine knocking?
2 Answers
The solutions for engine knocking are: 1. If knocking sounds occur in low-temperature environments after starting the car but disappear as the temperature rises, this type of knocking can be temporarily ignored, and driving can continue; 2. If the knocking sound persists and becomes more pronounced after the engine reaches normal temperature, the owner should avoid high-speed driving, promptly stop to inspect, and prevent traffic accidents; 3. If severe cylinder ovality, scoring, or excessive clearance between the piston and cylinder is found after removing the cylinder head and extracting the piston, replacement is necessary—replace the cylinder liner, piston, and piston rings; 4. If connecting rod deformation is detected, replacement should be prioritized.
Don't panic when encountering engine knocking. Every time I face this issue, I first check the engine oil condition. If the oil level is low or hasn't been changed for too long, insufficient lubrication between pistons and cylinder walls can cause that tapping sound - just top up the oil or do a complete oil change. If the noise persists, consider whether the piston ring gap is too large. In this case, you'll need to disassemble the engine and replace parts. I've done this twice myself - you'll need feeler gauges to measure the clearance, and it's safer to replace the piston pin bushings while you're at it. Another possibility is excessive carbon buildup causing detonation. Using fuel system cleaner and highway driving to burn off deposits works well, or you can disassemble for more thorough cleaning. If knocking occurs right after an engine overhaul, it's usually due to improper assembly clearances requiring readjustment of piston gaps. When all else fails, don't hesitate to do a complete overhaul - it's better than letting minor issues escalate into needing an engine replacement.
