What Causes the Metal Friction Sound in the Engine Compartment?

1 Answers
DeColeman
07/30/25 3:28am
Introduction to the causes of metal friction sound in the engine compartment: Hydraulic lifters: If the oil pressure is too low or the hydraulic lifters themselves are worn, air entering the lifters can cause a metal friction sound when starting the car. Worn valve rocker arms: Excessive wear on the valve rocker arms leading to excessive clearance or too much sludge and carbon buildup, or a dirty throttle body can also cause a metal sound during cold starts. Improperly installed engine front cover: During cold starts, the output power increases, and the engine noise correspondingly increases, which is normal. However, if the noise is too loud, you can mention this situation during maintenance.
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