What is a common symptom of a worn camshaft?

A common symptom of a worn camshaft is increased engine noise. This can occur because the camshaft is responsible for controlling the timing of valve openings and closings. When the camshaft wears down, it can result in improper clearances between the cam followers and the valvetrain components. This misalignment and increased play can lead to knocking, ticking, or grinding noises as the components do not operate smoothly as they should.

While sluggish acceleration and excessive oil consumption can also be issues in engines with worn components, they are not as directly associated with a worn camshaft as increased engine noise is. Sluggish acceleration could stem from a variety of factors including issues with fuel delivery or problems with other engine components, whereas excessive oil consumption might be attributed to worn piston rings or valve seals. Therefore, increased engine noise is the key symptom that distinctly signifies camshaft wear.