Sometimes there are warning signs before a timing belt breaks, but most belts fail with little or no notice. Possible symptoms include ticking or slapping noises from the timing cover area, rough running, misfires, hard starting, loss of power, or a check engine light related to timing problems. If the belt can be inspected, cracks, fraying, missing teeth, glazing, or oil contamination are serious red flags. However, a timing belt can appear acceptable in one visible section yet be weak elsewhere. That is why mileage and age matter more than waiting for symptoms. If your vehicle is near the manufacturer's recommended service interval, or you do not know when the belt was last replaced, schedule an inspection as soon as possible.