Timing Chain and Sprocket Noise

The most common noise is a high frequency, light-knocking sound. This sound will generally be the same in intensity whether the engine is idling, operating at high speeds, or under load. Causes of timing chain and sprocket noise include:
- Worn timing chain and/or gears
- Misaligned gears
- Excessive backlash
- Damaged tooth
- Gear or sprocket loose on shaft
- Too much end play in the camshaft or crankshaft
- Tensioner not functioning properly
- Loose or improperly seated camshaft timing gears are usually loudest when warm. They are speed sensitive only, not load sensitive.
- Cam gear noise will usually be evident at a warm idle in neutral and sounds much like a loose timing chain noise.