- 1). Be aware of changes in the performance of your vehicle's engine. An engine that frequently stalls or backfires, runs roughly with excessive vibration or produces noticeably less power may have a failing timing belt.
- 2). Note any squealing sounds or signs of smoke. These symptoms are telltale indications of a bad belt.
- 3). Have a mechanic visually inspect your vehicle's timing belt. Since timing belts are typically inaccessible and hard to see, this is a job for a professional. The belt should be replaced if there are cracks, fraying or other signs of damage.
- 4). Turn the key. If the engine cranks over unusually fast without starting, the timing belt is likely broken.
- 5). Remove the engine's distributor cap and see whether the rotor moves when the crankshaft is hand-turned. A lack of movement will confirm that the timing belt is bad.
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