Timing belts are the part of a car’s engine that synchronizes the rotation of the crankshaft and camshaft so that the engine’s cylinders fire at exactly the right time. A damaged or broken timing belt can cause big problems like piston damage, ruined cylinder head hardware, and engine valve damage. Timing belts will usually fail for one of two reasons: wear and tear due to age, or a faulty water pump. The timing belt is a rubber toothed belt, that can get brittle and crack over time, which can lead to it snapping. Since the timing belt runs through the water pump, it can also become damaged if the water pump malfunctions.
Some newer cars come with a timing chain, which is different than a belt because it is made of metal, and is therefore much less likely to break or need replacement. You should check your vehicle’s owner manual to know if your vehicle has a timing belt or timing chain. Timing belts are difficult to inspect because they are sealed in a protective cover. Therefore, it is important that you know the warning signs of problems with your car’s timing belt, and when to have it checked out by a professional.
- You hear a clicking noise from the engine. Timing belts are attached by a pulley system to your car engine’s crank and camshaft. When the timing belt is worn out, it can create a clicking or rattling sound from this pulley system inside the motor. This sound can also be a result of low oil pressure, which directly affects the timing belt. There is a tensioner that keeps the timing belt taught. If the tensioner doesn’t have proper oil pressure, the belt will become loose and possibly disengage from the pulley system or break.
- The engine won’t turn over. If the timing belt is broken, your car won’t start. When you turn the key, the starter motor might engage, but because the timing belt controls the crank and camshaft, the engine can’t turn over.
- Intermittent chirping noise. If you are hearing a chirping or squealing sound coming from your engine, this usually indicates a misalignment in the timing belt’s pulley system. This happens when a worn-out timing belt becomes glazed over and loses its ability to stay tight around the pulleys. These sounds can also be caused by failing bearings in the water pumps or slippage of one of the other engine belts (Serpentine or V-belt). Since the timing belt is toothed, it is not as subject to slippage as compared to the other engine belts.
- The engine misfires or runs rough. A worn-out timing belt can affect the engine’s timing, causing it to misfire. This happens when the belt slips, causing one of the engine cylinders to close or open earlier than normal. An engine even minimally out of time can idle roughly because the spark is not synced up with the cylinders.
A faulty or broken timing belt can cause disastrous engine damage to your car. If you notice any of these signs of a problem with your car’s timing belt, it is time to have your vehicle inspected immediately by a certified auto mechanic. Even if you don’t notice any of these symptoms of a faulty timing belt, it is generally recommended that you change your car’s timing belt and water pump about once every 4 years.