10 Bad Timing Chain Symptoms (How to Check)

Timing chains play a vital role in the internal mechanism of an engine, without which proper synchronization between the crankshaft and camshaft would be impossible. The said process is particularly crucial for interference-type OHC engines. For these power mills to function optimally, proper timing is a necessity. Otherwise, they would suffer internal damage — thus bringing us to the focus of this article.

Understanding telltale signs of a bad timing chain and knowing what and where to scrutinize is essential to the proper upkeep of this component. Spotting its symptoms early on, which include misfires, unusual engine noises, and impaired performance (to name a few), is equally important.

This guide may not be able to present an exhaustive list of warning indicators associated with timing chains. But for purposes of familiarity with the issue, here are the most prevalent bad timing chain symptoms:

1. Engine Misfires
2. Metal Rattling Noise
3. Contaminants in the Engine Oil
4. Diminished Power and Performance
5. Backfiring
6. Engine Overheating
7. Reduced Fuel Efficiency
8. Activated CEL and DTCs
9. Lifter Tick Sound
10. Stalling or Starting Difficulties

While they can be averted through regular maintenance and inspection, most of these symptoms are not as straightforward as we would like to think. Many are not exclusive to timing chain problems and would require further investigation. Meanwhile, others are not even amendable through repairs and would almost immediately warrant prompt replacement.

Either way, correctly identifying the symptoms is half the resolution done. So sit back and read on if you want to be further acquainted with these red flags.

Symptoms of a Bad Timing Chain

1. Engine Misfires

If your timing chain has slack or is off by one tooth, you may notice engine misfires becoming more and more frequent. This is because a timing chain stretched beyond normal or one that has skipped teeth typically results in incorrect valve timing. This out-of-sync timing causes the intake or exhaust valves to open or close at incorrect intervals, triggering the misfires.

Because misfiring is typically ignition-related, it is best to prioritize checking on ignition components at the first instance of this symptom. Once they check out, proceed with examining relevant fuel system elements. Doing this step should enable you to pinpoint whether the problem source is the timing chain or something else.

2. Metal Rattling Noise

A noticeable rattling noise from the engine bay, especially during idle or acceleration, can indicate a loose or failing timing chain. The noise is typically caused by excessive chain slack or worn-out chain guides.

You may think this is nothing new, and you are absolutely right! But make no mistake — this rattling noise is as dangerous as things can get with your timing chain.

This noise is typically intermittent and becomes noticeable during cold starts but diminishes as the vehicle reaches normal operating temperatures. In some cases, however, it can become particularly vexing and occur more persistently.

You would never want to ignore this symptom when it reaches this point since it can only mean one thing — the timing chain may be skipping a few teeth at a time, resulting in the collision of valves and pistons or, worse, internal engine damage.

3. Contaminants in the Engine Oil

When we say engine oil contamination, we do not mean oil mixing with fuel or coolant. Instead, we refer to metallic particles floating around in the oil filter and oil pan (view on Amazon). The downside to this symptom is that it is not exactly apparent — unless you habitually flush your oil reservoir before refilling it with a fresh one.

If you are wondering where these shavings come from, they are usually bits and pieces of the chain tensioners’ degraded plastic components. This debris sometimes makes its way into the reservoir and oil pan. Oil filters should stop these particles from traveling to areas within the engine they should not be in. But often, oil filters fail in this task because they themselves are compromised.

Metal shavings in the engine oil are never a good indication. Not only does it necessitate major overhauling and inspection, but it can also signify that your timing chain is seriously amiss and experiencing internal damage.

4. Diminished Power and Performance

A malfunctioning timing chain has been proven numerous times to result in reduced acceleration, unresponsiveness, and a noticeable decrease in overall power output.

When a tensioner breaks, it can cause the timing chain to jump, leading to a collision between valves and pistons. This catastrophic event can lead to severe engine damage, rendering your power mill unusable.

This issue often stems from worn-out or low-quality plastic components that may break over time. Unfortunately, certain engine models are known for tensioner failures — hence, it is crucial to thoroughly investigate this concern and check on TSBs if you suspect owning the engine in question.

5. Backfiring

When the timing chain is worn or stretched, it can disrupt the precise timing of the valve openings and closings. This misalignment results in combustion process disruption and, ultimately, engine backfires (those loud bangs or pops from the exhaust).

The main cause of backfiring is the faulty synchronization between the engine’s valves and pistons — which would not occur if the timing chain is flawless and in good working condition.

6. Engine Overheating

A bad timing chain disrupts not only the engine’s combustion process but also its cooling capabilities, leading to inadequate coolant circulation and eventual overheating. So if you notice the temperature gauge consistently in the red zone or your engine temperature rising quickly, a compromised timing chain may be to blame.

Of course, cooling system components should always be among the first to inspect in situations like this. But if they check out, you know the problem source could be inside your engine.

7. Reduced Fuel Efficiency

Like most of the preceding timing chain symptoms, poor fuel economy also stems from the faulty synchronization of the engine’s internal components. However, it differs in that it results in inefficient fuel burning and higher fuel consumption than usual.

Because the timing chain is in bad shape, the power mill may need to work harder to compensate for its flaw, resulting in a noticeable decrease in fuel efficiency and tank mileage.

8. Activated CEL and DTCs

Like most vehicular problems, a failing timing chain can set off the Check Engine Light on the dashboard. Irregularities in the timing chain’s operation can trigger the power mill’s sensors to send error codes to the vehicle’s onboard computer.

The Diagnostic Trouble Code (DTC) or fault code that commonly indicates a problem with the timing chain is P0016: Crankshaft Position Camshaft Position Correlation Bank 1 Sensor ‘A.’ As its description implies, this code is specific to the CMP-CKP correlation and indicates a malfunction or discrepancy in the timing relationship between the two sensors. P1391 Diagnostic Trouble Code may also come up. However, it is often indirectly related to timing chain issues.

A deteriorated timing chain can cause the camshaft and crankshaft to be out of sync, triggering either the P0016 or P1391 code. Often, these trouble codes occur alongside some of the other symptoms in this guide, like engine misfiring, rough running, decreased power output, poor fuel efficiency, and possibly an illuminated Check Engine Light.

While the P0016 code is more often attributed to issues with the timing chain, it can also be prompted by incorrectly installed sensors, electrical or wiring issues, ECM malfunction, or problems with the timing chain tensioner or guides. That said, a DIY approach may not always be ideal. In such situations, I recommend seeking assistance from a professional mechanic or technician.

9. Lifter Tick Sound

A lifter tick is one of the many routes that a degraded timing chain can go. And because its occurrence is largely contingent on the severity of damage incurred by the timing chain, it is regarded as one of the more significant warning signs among all the symptoms outlined in this guide.

When a timing chain becomes loose or worn, it can result in improper valve lift or uneven rotation of the camshaft, eventually leading to irregular deterioration of the valve lifters or a lifter tick. In certain instances, these similar circumstances can culminate in a more catastrophic engine failure.

Because the lifter tick is not exclusive to a bad timing chain, it is essential to conduct a thorough inspection to determine its underlying cause. Other contributors to a lift tick sound include worn lifters, compromised valve train components, and low oil pressure.

10. Stalling or Starting Difficulties

In severe cases, a degraded (and often neglected) timing chain can cause the engine to stall or refuse to start altogether. At this stage, the timing chain has stretched to a degree where it can no longer maintain proper timing, leading to a complete engine shutdown and sometimes damaging other engine components.

Earlier warning signs leading to this point may include sporadic instances of your car not starting after being topped up at the pump station or any of the other telltale indicators listed here. So, when you hear that occasional rattling or observe a notable decrease in engine responsiveness or power, promptly diagnose the suspected components and address the issue without delay.

Staying on Top of Timing Chain Issues

To avoid severe engine damage and costly repairs, it is crucial to be vigilant over timing chain maintenance. Addressing these issues promptly via regularly scheduled engine check-ups and adherence to OEM-recommended service intervals is the goal.

Ultimately, you would want to be a step ahead and prevent their occurrence (and the below practices can help you do just that):

• Replace your timing chain on time. Depending on your vehicle’s year, make, and model, it should be replaced once it hits 80,000—100,000 miles.
• Never postpone those scheduled oil changes. Because of how it operates, your timing chain constantly requires fresh oil to run well.
• Refrain from using your vehicle when it is running low on oil. Doing so messes with heat dissipation and may cause friction-prone, moving components like rod bearings and piston rings to malfunction.
• Determine what kind of timing chain tensioner your vehicle has from the get-go, and only use OEM-recommended high-quality engine oil for lubricating powertrain components to contribute to your timing chain’s longevity.
• Be intentional with your driving habits. Although tempting, stop yourself from running your engine at high RPMs for extended periods.

How Do You Check a Timing Chain?

Steps for checking a suspected timing chain are usually contingent on your vehicle’s make and model and the OEM’s recommendations. Nonetheless, here are general guidelines that you can follow if you are technically savvy in carrying out initial diagnostics and getting things done:

1. Let the Engine Cool Down

Ensure your vehicle is on a level surface, with the engine off and the key removed from the ignition. After which, let the engine cool down for at least 30 minutes to an hour before proceeding.

2. Listen for Unusual Noises

Pay attention to any rattling, ticking, or clattering sounds coming from the engine compartment, particularly when the engine is idling, revving, or accelerating.

3. Open the Chain Cover

Access the timing chain cover typically located on the front of the engine. Next, carefully remove the bolts or fasteners securing the timing chain cover. Take note of the positions of these attachment aids, as some may have different lengths.

Gently pry open the chain cover using a flathead screwdriver prybar (view on Amazon) or other suitable tool. While at it, examine the timing chain cover for signs of oil leakage typically suggestive of a deteriorating chain tensioner or guide.

4. Inspect for Damage

Once the timing chain cover is removed, begin your visual inspection of the timing chain. Look for damage, excessive wear, stretching, or broken links. Also, check for proper tension and alignment.

Depending on your vehicle specs, you may need to remove other components, such as the serpentine belt or engine casings, to gain access to the timing chain cover (at this point, you would have already completed these additional steps anyway).

5. Check the Tensioner

If your vehicle is a more recent model, it likely has an automatic timing chain tensioner (view on Amazon). That said, check that the tensioner is properly applying the right amount of tension to the timing chain. Apply gentle pressure to the chain with a wrench and observe its movement.

Excessive looseness or movement could indicate significant wear and the need for immediate replacement. Similarly, if the tensioner is faulty or not providing sufficient tension, it should be addressed promptly.

6. Examine the Chain Guides and Sprockets

Inspect the chain guides and sprockets for wear or damage, paying attention to excessive wear on the guide rails and sprocket teeth. If significant wear is present, replacement of the guides or sprockets may be necessary.

7. Confirm Proper Alignment

Verify proper alignment of the timing chain with the camshaft and crankshaft. The timing marks on the sprockets should line up with the corresponding marks on the engine, similar to how you would set the ignition timing on a 4×4 Jeep.

8. Reinstall the Timing Chain Cover

Provided the preceding steps have been executed to the T, proceed with reinstalling the timing chain cover.

Clean the chain cover and engine block mating surfaces, apply a new gasket or sealant per OEM instructions, and carefully reinstall the timing chain cover. Make sure to replace the bolts or fasteners in their correct positions and tighten them to the specified torque.

9. Do a Final Inspection

Give your timing chain assembly one final inspection, double-checking all connections, components, and hoses removed during the process. Ensure that everything is properly reassembled and secured and that deteriorated parts are all replaced accordingly.

Note that maintaining the timing chain requires a certain level of automotive knowledge and expertise, and sometimes the issue would still resurface despite completing the above steps.

So whenever you are uncertain about performing the checks yourself (or the timing chain issues persist), do not hesitate to consult a qualified mechanic or technician who can conduct a more thorough inspection and diagnosis of the erring component.

Timing Chain Replacement Cost

The cost to replace a timing chain can vary depending on the vehicle, the accessibility of the timing chain, and the labor rates in your area. On average, timing chain replacement expenses can range from $400 to $800, including parts and labor. For high-end and luxury vehicles, however, you can expect this price range to double — from $1,000 to $2,000.

However, your expenses are not necessarily limited to the timing chain alone. Depending on how far gone the timing chain issue is and whether other components are affected, you may need to shell out more than the price of a brand-new timing chain.

If you are experiencing engine misfiring and require new spark plugs, you are in luck. But if you are experiencing engine overheating, for instance, you may need to allocate an extra $150 to $1,800 for a possible thermostat, radiator (view on Amazon), or water pump replacement.

Conclusion — Bad Timing Chain Symptoms

To summarize, here are 10 bad timing chain symptoms you should keep an eye out for:

1. Engine Misfires
2. Metal Rattling Noise
3. Contaminants in the Engine Oil
4. Diminished Power and Performance
5. Backfiring
6. Engine Overheating
7. Reduced Fuel Efficiency
8. Activated CEL and DTCs
9. Lifter Tick Sound
10. Stalling or Starting Difficulties

While a vehicle can run with a bad timing chain, it is ill-advised. Not only can ignoring timing chain issues lead to severe engine damage like bent valves or damaged pistons, but its complications can significantly escalate repair costs.

More importantly, knowingly driving with a bad timing chain is counter-intuitive as it substantially raises the risk of sudden engine failure and the likelihood of on-road accidents.