The timing chain tensioner is an integral part of the engine that helps keep the timing chain in place. If this part goes bad, it can cause a lot of damage to the engine and lead to costly repairs. This article will discuss the symptoms of a bad timing chain tensioner and how to replace them if they go bad. We will also discuss the replacement cost of these parts and answer some of the most frequently asked questions about them.
A failing timing chain tensioner can cause several symptoms, including engine misfires, a loss of power, and strange noises from the engine. If you notice any of these symptoms, it’s important to have your car checked out by a mechanic as soon as possible to avoid further damage.
Table of Contents
What is a Timing Chain Tensioner?
Before we can understand what a timing chain tensioner is and what purpose it serves, it is important to know what is a timing chain and its function. A timing chain is a critical component of an internal combustion engine that synchronizes the rotation of the crankshaft and camshaft. It is just like a normal bicycle chain with small links attached to one another with pins.
Timing chain systems ensure that the engine’s valves open and close at the correct time in relation to the position of the pistons. If the timing chain stretches or snaps, it can cause serious damage to the engine. A broken timing chain can sometimes result in catastrophic engine failure.
Now, a timing chain tensioner is a device used to maintain proper tension on the timing chain. The timing chain tensioner keeps the timing chain tight, so it does not skip or jump teeth on the sprockets. A properly functioning timing chain tensioner is critical for maintaining the proper function of an internal combustion engine.
How Do Timing Chain Tensioners Work in the Internal Combustion Engine?
The timing chain tensioner is located at the front of the engine, and it is actuated by engine oil pressure. The timing chain tensioner is designed to apply pressure to the timing chain, so it remains tight against the sprockets.
The pressure is applied through a spring-loaded plunger that pushes on the chain. As the engine runs, the plunger is forced back and forth by the movement of the timing chains. This action keeps the chain tight against the sprockets, preventing it from becoming loose.
Over time, however, the spring inside the tensioner can weaken, and the plunger may not be able to apply enough pressure to keep the chain tight. When this happens, the timing chain will begin to loosen, and the engine will run poorly as a result. In some cases, a loose timing chain can cause the engine to stall completely.
Bad Timing Chain Tensioner Symptoms
Several symptoms can indicate the timing chain tensioner failure. These include:
- Check Engine Light
- Knocking Noise
- Worn Timing Chain
- Engine Misfires
- Car Won’t Start
- Poor Engine Performance
Let us explain these symptoms a bit:
1. Check Engine Light:
The check engine light may illuminate if there is an issue with the timing chain tensioner. If the tensioner is not working properly, it can cause the timing chain to skip a tooth or jump a cog, which will trigger the check engine light. Although there are many potential causes of a check engine light, a defective timing chain tensioner is one possibility.
The reason behind the illumination of the check engine light is the deviation of senors input and the output value from the normal range. For example, if the oxygen sensor detects that the engine is running leaner than normal, it will send a signal to the Engine Control Unit (ECU). The ECU will then turn on the check engine light to alert the driver of the problem. A bad timing chain tensioner may disrupt the normal functioning of various sensors, including the camshaft and crankshaft sensors, which can cause the check engine light to come on.
If you notice that the check engine light is illuminated on your dashboard, it is crucial to take your car to a mechanic to have it diagnosed. The mechanic will hook up a diagnostic tool to the car’s computer and run a diagnostic test. This will help pinpoint the problem and determine whether or not the timing chain tensioner is the cause.
2. Knocking Noise:
One of the most common symptoms of a bad timing chain tensioner is a knocking noise from the engine. The timing chain noise is caused by the timing chain slapping against the inside of the engine. This can happen if the timing chain is loose or if it has jumped a tooth on the sprocket.
If the timing chain tensioner is failing, it will not be able to keep the timing chain tight against the sprockets. This can cause the chain to slap against the inside of the engine, resulting in a knocking noise. A broken timing chain will also cause a knocking noise as it tries to turn the camshaft and crankshaft at the same time.
3. Worn Timing Chain:
If the timing chain tensioner is not working properly, it can cause the timing chain to wear out prematurely. The timing chain is located in a high-stress area of the engine and is subject to a lot of vibration. If the chain is not kept tight by the tensioner, it will begin to stretch and wear out prematurely. Thus, if you have a stretched timing chain it is time for timing chain tensioner replacement.
4. Engine Misfires:
Another symptom of a timing chain failure is engine misfires. Bad timing chain tensioners are one of the most common causes of engine misfires. If the tensioner does not keep the timing chain tight, it can cause the engine to misfire. The timing chain connects the camshaft to the crankshaft and controls when the spark plugs fire. If the valve timing is not in sync, it can cause the spark plugs to fire at the wrong time, resulting in an engine misfire.
An engine misfire can cause several problems, including poor fuel economy, increased emissions, and damage to the catalytic converter. If you notice that your engine is misfiring, it is important to take it to a mechanic to have it diagnosed.
5. Car Won’t Start:
If the timing chain tensioner is not working properly, it can cause the car not to start. The timing chain is responsible for synchronizing the camshaft and crankshaft. If the chain is not tight, it can cause the engine not to start. A loose or broken timing chain will also prevent the engine from starting.
6. Poor Engine Performance:
A timing chain problem can cause many issues with your engine, including poor performance. The timing chain is responsible for keeping the pistons and valves in sync, and if it is not properly tensioned, it can cause the engine to run erratically or even stall. In some cases, a bad timing chain tensioner can also cause damage to the engine itself.
Causes of a Bad Timing Belt Tensioner
As we mentioned before, a timing belt tensioner is actuated by engine oil pressure. Over time, the oil pressure in the engine can drop, causing the timing chain to loosen. This will eventually lead to the symptoms listed above. However, let us see the causes of failure for the timing belt tensioner in detail:
1. Wear and Tear:
The timing chain tensioner consists of a spring-loaded piston that is pushed against the side of the timing chain by hydraulic pressure. The piston has a small hole in it that allows oil to flow through and keep the piston lubricated. As the engine runs, the oil pressure pushes against the piston, keeping the tension in the timing chain constant.
Over time, however, the oil pressure can drop due to normal wear and tear. When this happens, the timing chain can become loose and cause the engine to misfire. In some cases, the timing chain can even come off completely, which will cause the engine to seize up.
2. Debris in Engine Oil:
Another common cause of a bad timing chain tensioner is debris in the engine oil. As the engine oil breaks down, it can form sludge and deposits that can clog up the small hole in the piston. When this happens, the oil pressure can drop, causing the timing chain to become loose. In some cases, the debris can also cause the piston to seize up, which will result in the engine stalling.
3. Wrong Adjustment of Tensioner:
The timing chain tensioner is a vital component in the engine, and its correct adjustment is crucial for its proper operation. If the tensioner is incorrectly adjusted, it can cause the chain to become loose, which can lead to serious engine damage. An incorrectly adjusted tensioner can also cause the chain to break, resulting in catastrophic engine failure. Therefore, it is important to ensure the tensioner is properly adjusted before operating the engine.
4. Engine Overheating:
If the engine overheats, it can cause the timing chain tensioner to fail. The timing chain tensioner is responsible for keeping the timing chain tight and in proper alignment. If the engine overheats, the metal components of the timing chain tensioner can expand and cause the chain to become loose or misaligned. This can lead to engine failure.
Overheating can also cause engine problems such as warped cylinder heads or blown head gaskets. These problems can also cause the timing chain to become loose or misaligned.
Sensors and Timing Chain
The working of the timing chain in an internal combustion engine is affected by various sensors. Two of the most important sensors include the crankshaft and camshaft position sensor. Let us see how they relate to the working of the timing chain:
Crankshaft Position Sensor
A crankshaft position sensor is a type of engine sensor that helps determine the position of the crankshaft. The position of the crankshaft is important to the proper functioning of an engine because it helps control the timing of the engine’s valves. The sensor is usually a magnetically-sensitive device mounted on or near the crankshaft. As the crankshaft rotates, the sensor’s magnetic field changes, which is used to determine the position of the crankshaft.
Camshaft Position Sensor
A timing chain is a metal chain that connects the crankshaft to the camshaft and ensures that the pistons and valves in an engine are in sync. The timing chain is an essential component of the engine, and if it breaks, the engine will not be able to run.
The camshaft position sensor is used to determine the position of the camshaft and is typically located near the top of the engine. The sensor sends a signal to the computer, which tells it when to fire the spark plugs and open the valves. The engine will not run correctly if the sensor is not working properly.
How to Reset a Bad Timing Chain Tensioner?
Replacement or resetting the timing chain tensioner is one of the most challenging jobs on any vehicle. The problems faced while replacing a timing chain tensioner are:
1. Adjustment of timing chain:
This part requires the highest level of skill. If the timing of the chain is even out by a single tooth, it can cause many problems with the engine.
- Engine misfire – When a timing chain breaks, it can cause the engine to misfire. This is because the broken timing chain can no longer keep the valves in sync with the pistons.
- Damage to the valves – The valves are responsible for controlling the flow of air and fuel into the cylinders. If the timing chain breaks, it can cause the valves to come into contact with the pistons, which can bend or break them.
- Engine failure – In extreme cases, a broken timing chain can cause the engine to fail completely. This is because the engine will be unable to maintain proper timing, which will cause it to seize up.
If you think that your vehicle’s timing chain may have skipped a tooth or two, it’s important to have it checked out by a professional as soon as possible. If the problem is not fixed, it could lead to severe engine damage or even failure.
2. Matching the old tensioner with the new one:
Different types and sizes of timing chain tensioners are available in the market. So, finding an exact match for the old tensioner becomes difficult. Due to these issues, this replacement is best left to professionals.
Timing Chain Tensioner Replacement Costs
The timing chain tensioner is one of the most critical components of the internal combustion engine. Plus, its replacement is no easy task. This job requires special tools and knowledge to install the new tensioner properly.
Timing chain replacement cost will vary depending on the make and model of your vehicle. On average, you can expect to pay between $600 and $1,000 for this repair. Keep in mind that this is just an estimate. The actual cost could be more or less depending on your specific circumstances.
Labor costs are estimated between $500 and $700, while parts are priced at $200 to $300. This range does not include taxes and fees and does not factor in your unique location. You may also need related repairs.
You can expect to pay on the higher end of the price range if you have a late-model car with a complex engine. If you have an older car with a simpler engine, you may be able to get by at a lower price. In either case, it’s always a good idea to get multiple quotes from different mechanics before making a final decision.
Conclusion
A damaged or faulty timing chain tensioner can cause several problems with your vehicle, including engine damage. If the timing chain tensioner fails completely, it can also cause the timing chain to come off entirely. This can lead to catastrophic engine damage and, in some cases, even engine failure.
It is important to have your timing chain tensioner checked regularly by a qualified mechanic to ensure it is functioning properly. If you suspect that your timing chain tensioner is not working properly, have it checked as soon as possible to avoid potentially serious engine damage.
Frequently Asked Questions
What happens when the timing chain tensioner fails?
When the timing chain tensioner fails, it can cause the timing chain to become loose and eventually fall off. This will cause the engine to misfire and possibly stall. In some cases, it may also cause engine damage.
Can you drive with a bad timing chain tensioner?
A bad timing chain tensioner can cause many engine performance issues, eventually leading to engine failure. It is therefore not advisable to drive with a bad timing chain tensioner. You must have the problem fixed by a qualified mechanic as soon as possible.
What does a bad timing chain tensioner sound like?
If your car has a bad timing chain tensioner, it will usually produce a ticking noise from the engine. The noise will be most noticeable when the engine is idling or running at low speeds. In some cases, the timing chain may also rattle when the engine is first started. If the problem is severe enough, it can eventually cause the timing chain to break, which will result in catastrophic engine damage.
How long does the timing chain tensioner last?
Most timing chain tensioners are designed to last the life of the engine, but some may need to be replaced sooner if they become worn or damaged. Hence, checking the timing chain tensioner every 10,000 miles is recommended after your vehicle has crossed 40,000 miles. However, you must consider replacing it once you are past the 100,000 miles mark.
In addition to regular maintenance, you can extend the life of your timing chain tensioner by avoiding extended periods of idling and driving at low speeds. These habits put unnecessary strain on the tensioner and can cause it to fail prematurely. If you must drive in these conditions, take a break every so often to let the tensioner cool down.
Can you replace a car’s timing chain tensioner yourself?
Replacing a timing chain tensioner is a complex job that should only be attempted by a qualified mechanic. If you are not experienced in engine repairs, it is best to leave this job to the professionals.
If a timing chain breaks, how long does it take to replace it?
An expert mechanic may take 5 to 8 hours to replace a timing chain, depending on the make and model of your vehicle. On the other hand, a novice could take up to 12 hours.
How to Prevent a Timing Chain Tensioner from Going Bad?
The best way to prevent a timing chain tensioner from going bad is to change the engine oil regularly. This will ensure that the oil pressure remains high and the timing chain remains tight. In addition, you should also check the engine oil level on a regular basis and make sure that it is not low.
