Symptoms of a Bad Timing Chain - Symptoms and Fixes | REV (2023)

Technological advances in the automotive industry have allowed automakers to replace rubber toothed belts with more sophisticated toothed chains. The metal chain plays a key role in opening the engine valves in time, and its dynamic role in the engine makes it vulnerable to damage.

Therefore, it is important to answer after hearing the first onetiming chain symptomertells you it's time to change the chain. It's always good to know how a broken timing chain will affect your engine's functionality, so our team decided to give you a detailed breakdown of the biggest symptoms.

What is a time chain and what is it for?

Your car's timing chain is an engine-mounted metal chain that rotates between gears in the engine to move some important mechanical components. It connects the crankshaft and camshaft to open the valves and precisely control the pistons.

Thanks to the chain, everything runs smoothly in the engine's ignition cycle. This ensures that the engine pistons do not hit the valves, which can cause the engine to stop. So it is one of the key elements of your car's mechanical system.

If the timing chain breaks, the pistons will hit the valves and damage the engine, resulting in an expensive engine rebuild. Most modern cars have timing chains developed from timing belts that serve the same purpose but are more sensitive to heat.

The toothed chain is lubricated with engine oil, which prevents wear in contact with the gears in the engine. However, sometimes damage can occur and it is important to act quickly in this case.

The difference between toothed belts and toothed chains

Although both serve the same role in an engine, timing chains are much more durable than timing belts. Timing belts are most commonly used on cars with small displacement engines and older models, while more powerful engines tend to have timing chains.

The timing belt is also rubbery and the chain is, you guessed it, a metal chain. So you don't have to worry about the belt freezing in cold weather or wearing out due to high engine temperatures over time.

These are all disadvantages of toothed belts, so you would think that toothed chains could last forever. Well, some manufacturers certainly claim that their chains really should last forever as long as the engine oil is changed frequently. However, this is not always the case, as the chain can also be damaged.

One of the advantages of driving a car with a timing belt is that the engine runs more quietly compared to cars with a timing belt. Timing belts should be replaced every 5 or 6 years or every 60,000 to 100,000 miles. Timing chains, on the other hand, last much longer if properly maintained. Still, if you're unfortunate enough to keep your timing chain running for the life of your vehicle, we'll cover the signs of bad chains.

The main signs of a bad timing chain

One of the biggest signs of a bad timing chain is rattling when the engine idles. At this point, if you are notacceleration of the car, the engine must run smoothly without noise or speed jumps. So if you hear this noise and the RPM goes up and down at idle, it could be a sign that the timing chain has skipped.

However, if your timing chain is broken, you will also likely experience the following symptoms:

• Metal pieces found during oil and filter changes
• Frequent misfires and loss of power
• Check if the check engine light is on
• Car starting problems

If your mechanic tells you that there are small pieces of metal in the oil or filters after changing the oil or filters, this could be a sign of a bad timing chain. Even if it's not the chain, it can damage the cylinder heads or other metal parts on the engine, so act fast.

Poor engine power and misfire

Engine misfire is another common symptom of a damaged timing chain. It gives poor acceleration when you step on the gas and you can feel that there is a blockage in the fuel delivery system. Misfires will feel like the engine suddenly loses power under acceleration, and you'll also feel it on the throttle.

This is a symptom that also appears due to a bad crankshaft position sensor or fuel delivery problems. You can even experience yoursturn off the car while driving and restart it. The sensor is easy to replace though, but if the crankshaft and camshaft are off due to a bad timing chain, this is a much bigger problem.

The chain can slip off the gears in the engine and damage other rotating components. So misfiring should always be taken seriously and have your engine checked by a mechanic.

The check engine light is a warning

If the "check engine" light is on on the dashboard, this is a common symptom of a bad timing chain. Mechanics often call this a "clue" to engine timing problems and poor performance. At least you have enough time to go directly to a mechanic with a scanner, or you can use the scanner yourself.

This way you can diagnose an engine fault by reading the code and if it says P0009 or P0012 it could be a timing chain fault. If you don't drive straight to a mechanic, your engine could fail within 5,000 miles of the light coming on.

It will start to fail first and the performance "clog" we mentioned earlier will become more and more frequent. Eventually the engine stalls completely because timing belt failure has caused the pistons to hit the valves. After this time you will not be able to start the car and the only solution left is to rebuild the engine.

Our position

Finally, if you experience any of the timing chain symptoms described in this guide, do not hesitate to visit a mechanic. This should not be taken lightly as a damaged sprocket can seriously damage the engine.

At least now you have an insight into the main symptoms of a bad timing chain, so you don't have to risk rebuilding your entire engine.