7 Symptoms of a Bad or Failing Timing Belt

Timing belts allow your vehicle’s engine to operate. They are in charge of synchronizing the rotation system of the engine’s camshaft and crankshaft, in order to enable engine valves to open and close at the right time.

These car parts are subject to great forces inside the vehicle’s engine. For this reason, every vehicle that has a timing belt will require a new timing belt replacement at some point during its life. Without a fully functioning timing belt, the car’s engine won’t be able to run properly.

What Does a Timing Belt Do?

Your timing belt (cam belt) connects the crankshaft and the camshaft, coordinating the combustion cycle of an internal combustion engine.

The movement of the pistons rotates the crankshaft. The rotation of the crankshaft is transmitted through the timing belt to move the camshaft. The camshaft then controls the intake and exhaust valve activity.

Here’s what happens within a cylinder:

  • The cylinder’s intake valves open to allow air and fuel into the combustion chamber.
  • The camshaft then closes the valves, and the piston moves up in the cylinder, compressing the fuel/air mixture.
  • The spark plug ignites the mixture, and it explodes, forcing the piston to move back down the cylinder and rotating the crankshaft.
  • Then the camshaft causes the exhaust valve to open, allowing the exhaust gasses produced by the explosion to exit the cylinder, and the cycle repeats.

Each valve and piston must move in a carefully coordinated dance to work effectively without blowing up the engine.

Note: Your timing belt shouldn’t be confused with your serpentine belt. Your serpentine belt keeps your engine accessories running, and your vehicle’s timing belt handles the combustion cycle.

Signs Your Timing Belt Is Going Bad

There are a few warning signs that can help you diagnose when you need a new timing belt, but it is important to remember that prevention is the key to an optimal car maintenance, as there are no certain clues to indicate a worn belt that may be close to snapping.

symptoms of bad timing belt

Listed below are five key signs to be aware of that may help you determine if it’s time to check and get a new timing belt.

#1. Ticking Noise Coming from The Engine.

When the timing belt wears out, it can cause a ticking or clicking sound inside the engine. This sound can indicate low oil pressure, which can affect the timing belt. The tensioner that keeps the belt taut is pressurized by the engine oil.

If the tensioner has no oil pressure, the belt will become loose and possibly disengage from the pulleys and/or break. If the camshafts don’t have enough oil pressure to operate properly, they will also lock up, causing the timing belt to break.

#2. Your Car’s Engine Won’t Turn Over.

When the timing belt is broken you will not even be able to start your vehicle. You may hear a clicking sound when you turn the key, but the engine will not fire. This clicking is coming from the starter motor.

But when the belt is broken it won’t allow the crankshaft and the camshaft to operate. There are many times that you won’t even know that the timing belt has broken because in many cases the belt fails while driving.

#3. Notice an Oil Leak Near the Motor.

The timing belt is held in place by a series of nuts. However, over time, these can loosen. When this happens, it can cause an oil leak around the timing belt cover. As you can imagine, this can be a serious problem.

When the flow of oil is disrupted, there is a big risk that the engine might overheat. If this happens, it can lead to significant damage and a big repair bill.

#4. More Smoke and Fumes Than Normal.

Belt wear and stretching damages the catalyst, as the fuel is not completely burned in the chambers due to an incorrect composition of mixture fuel. That means: all the fuel that has not been consumed is directed to the exhaust system.

If you hear a clicking noise when starting the engine and see black smoke coming from the vehicle’s exhaust pipe, this indicates an incorrect fuel composition that may be due, among many others, to damage to the timing belt.

#5. If You Notice a Change in Your RPMs (Revolutions Per Minute).

If you’ve noticed that your RPMs (revolutions per minute) have started to act strange, it could be an indication that something is wrong with your timing belt. Whether your timing belt is missing teeth, or it has snapped completely, this can have a tremendous effect on your car’s RPM meter.

Unfortunately, sometimes there are no obvious signs that your car’s timing belt is need of repair. That’s why highly rated auto mechanics recommend replacing your timing belt every 60,000 to 100,000 miles. You can also check your owner’s manual for the manufacturer’s recommendation as well.

#6. Damaged pistons.

When the timing belt breaks up completely, it affects the movement of the crankshaft as well as camshaft, which in turn damages the piston, as it disturbs the movement of the pistons due to their abrupt movement. A bad timing belt hampers the overall working of a vehicle and can result in some serious damage to the engine.

#7. Your Check Engine Light Is On.

Depending on what car your drive, a problem with your timing belt might activate the check engine light. Though it’s one of the least dramatic warning signs, this light should never be ignored. It means that there is something wrong, and you should contact a mechanic as soon as possible.

What To Do If Your Timing Belt Breaks While Driving?

Your car cannot run with a broken timing belt. By the time the belt snaps, the damage is already done, and you will not be able to drive at all. You will need to have the vehicle towed to an auto repair workshop.

The question is, how long can you drive with a bad timing belt? Once you know that your timing belt is faulty – but it has not yet broken – can you still drive the car? It is possible to continue driving the car in this state, although there is a risk that the belt will snap at any time.

It really is not advisable to drive the vehicle for any significant length of time once you are aware that you may have a timing belt problem.