Harmonic Balancer Wobble – Symptoms, Causes & Solutions

Have you started experiencing some strange symptoms with your car and you are asking yourself if this is a harmonic balancer wobble (because you’ve heard from someone that’s a thing)? If that is the case, you are at the right place because there will be a lot to cover on this topic.

A harmonic balancer also known as a harmonic damper is a device that is installed on the crankshaft of the engine. This engine part is also known as the crank pulley, since it works also as an external balancer and as a pulley for the serpentine belt.

The location of this harmonic balancer in an FWD (front-wheel drive) configuration car is always on the left side of the engine bay at the bottom where the belt is mounted. While in RWD (rear-wheel drive) applications, this balancer is mounted at the front bottom of the engine, right between the radiator and the bottom of the engine.

What is worth noting is that not every engine has this type of device. For example, boxer engines as well as flat-plane V8s do not need a harmonic balancer. But other engines that are not internally balanced do need it.

When it comes to its role in the internal combustion engine, this component has the simple purpose of balancing the engine. Some engines have to be externally balanced and this is why they are using these devices in order to achieve smooth work and dampen the vibrations and stress that is created.

Symptoms Of a Wobbling Harmonic Balancer

Now let’s discuss the symptoms of the harmonic balancer and learn more about what kind of issues you are going to face whenever this harmonic balancer fails. Knowing these symptoms is crucial if you want to learn more about how to diagnose and fix the problem. So, let’s dive into the symptoms and elaborate them in-depth.

Symptoms Of a Wobbling Harmonic Balancer include:

  • Check engine light
  • Engine vibrations
  • Engine squeaking
  • Visible wobble of the harmonic balancer
  • Visible damage to the harmonic balancer
  • Symptoms disappear when speeding up

1. Check Engine Light

The first symptom is the check engine light. Although many people would think that it is counterintuitive but can happen when there is harmonic balancer wobble.

So, why could there be a check engine light when you have wobble? Well, this is the case because there is a knock sensor on the car that detects abnormalities in the cylinders and in the crankcase. Whenever there is a wobble, this sensor can be triggered because there will be a lot of vibrations.

In addition to this, the pulley can slip and cause problems with the accessories of the car. The battery might not charge because the alternator depends on this harmonic balancer. There are also some other accessories like the AC, power steering, and so on.

Whenever there is a wobble in the belt, these components might underperform and the PCM will detect these poor readings and might trigger the check engine light.

This is why we recommend that you should never ignore the check engine light and make sure that you always address it if it starts flashing or staying on all of the time.

2. Engine Vibrations

Another symptom of harmonic balancer wobble is the situation when you start to experience engine vibrations. Why will there be vibrations whenever there is a wobble in the balancer?

Well, because this balancer has a task to counterbalance the crankshaft of the engine. And imagine that the engine is rotating at 1,000 rpm at idle.

With the balancer out of position and wobbling around will result in more and more vibrations developing in the car and these vibrations will be present mostly on idle.

There will also be vibrations experienced throughout the cabin. Especially when you touch the gear lever which is directly connected to the transmission and the transmission as you know is connected to the engine that has a bad balancer that is producing vibrations.

3. Squeaking Noises

Another common symptom when you have a harmonic balancer wobble is the case when you start to experience squeaking noises. So, why is this the case?

This is the case mostly because this balancer drives the serpentine belt at the same time. So, when the balancer starts to wobble, the belt can also move around and this will develop squeaking noises.

These squeaking noises will be most prominent on startup and after the engine warms up, these noises should go away.

A lot of people think that this problem is caused by a bad belt tensioner or a poor serpentine belt. But this is not always the case, sometimes the pulleys can also cause the problem and overall, the harmonic balancer is one big pulley that transfers the energy of the crankshaft onto the serpentine belt.

4. Visible Wobble To The Harmonic Balancer

Another symptom associated with harmonic balancer wobble is the visible wobble of the balancer on idle.

Let’s say that you started the car and if you go and inspect the engine and you turn on the flashlight and point it to the balancer, you will notice how the harmonic balancer will move around.

A good harmonic balancer should not have any tolerance when it comes to wobble. So, even if the harmonic balancer moves ever slightly, you know that the balancer is bad and has to be replaced.

And it is important to react quickly because if you leave it like that, it could cause the belt to fail or separate from the engine.

In this case, you will lose all the accessories of the car and the car’s engine will simply shut down. And if you drive on the highway, you definitely don’t want to experience an engine stall at these speeds.

5. Visible Damage To The Harmonic Balancer

The harmonic balancer, even if it does not wobble, can still show some signs of wear and tear. So, how does this happen?

Well, this component is made from two pieces, an inertia mass, and an energy-dissipating element.

This energy-dissipating element is made out of rubber and rubber can crack. There are cracks that will form on the rubber and the rubber will start to fall apart.

If you make a close-up inspection, you will notice how the balancer has cracks on it. This is the rubber component.

Nothing too scary but it is important that you sort out the problem on time. In case these two elements separate, the balancer will start to slip and the belt will start moving.

This will result in engine stall in most cases. It cannot damage the engine. But it is still dangerous for you to experience a stall at high speeds as we noted. This is why we advise that you sort out the problem sooner than later.

6. Symptoms Disappear When Speeding Up

And the last symptom of harmonic balancer wobble is the situation when all symptoms associated with this problem simply disappear after you speed up the car. So, why is this the case?

Well, this is often the case because the crankshaft is rotating much faster. At idle the engine rotates at 600 to 800 rpm. When you apply the throttle, this speed can increase up to 7,000 rpm on some engines.

And the faster the crankshaft spins, the less symptoms you experience. There will be no squeaks, no serious wobble.

But this doesn’t mean that you don’t have a problem, you still have a problem and this problem needs to be sorted out.

Causes for Harmonic Balancer Failure

Now let’s elaborate more on the causes for the harmonic balancer wobble. Every problem has a cause, so let’s elaborate more on these causes for this problem to develop in your car. Knowing the causes, you might be somewhat able to avoid it.

Causes for Harmonic Balancer Failure include:

  • Age and time related deterioration
  • High mileage
  • Engine is prone to develop harmonic balancer problems

1. Age

The first and most common cause for the harmonic balancer wobble is definitely age. We noted that this component consists of metal and rubber parts.

Rubber doesn’t like age. Even after a few years, this rubber will harden as a rock from the immense heat that is created inside the engine bay.

These heat cycles will deteriorate the rubber and will ruin the balancer. There will be cracks that will develop and the balancer will eventually fail completely.

This is why if the car is older, it is recommended that you inspect the balancer and if the balancer is damaged, you will have to replace it with a new unit.

2. High Mileage

High mileage is another attributing factor for the harmonic balancer wobble and failure. The higher the miles the car has, the more likely you will have to replace the balancer.

These replacements are usually done at very high miles well above 200,000 miles. But they can also occur earlier.

This problem is also present in cars that idle a lot. For example, cop cars. Cop cars are working 24/7, so even if the car has low miles, there is a high chance that the balancer will wobble.

This problem is very common on Chevy LS engines used on the Chevy Caprice PPV and similar models.

3. Engine Is Prone To Develop Wobble

Harmonic balancer on some cars is also more prone to fail than on others. For example, BMW is not highly regarded for its quality harmonic balancers.

There are a lot of owners reporting replacing these components on their BMW N54/N55 engines as low as 67k miles. And the owner reported another failure on 125k miles. The harmonic balancers are also known to fail on Mercedes M112 engines.

So, if you are in the market for a BMW, you should make sure that you are aware of the problem since it can be expensive to be sorted out.

Harmonic Balancer Replacement Procedure

How difficult can it be to get this harmonic balancer replaced? Is this job DIY friendly or not? Can a beginner do this job?

Well, we can say that this is an intermediate-level job. This is the case because this balancer is not easily accessible.

In other words, there is a lot of work to reach this component and also this component does not give up without a fight.

The first component that will have to be removed is the front radiator since the radiator is located immediately next to the balancer on all RWD models.

This means that the coolant should be flushed and then the radiator removed, only then you can loosen up the tensioner of the serpentine belt and remove the harmonic balancer.

This balancer is also held by a very big bolt that is torqued. More than 200 ft-lbs to be more precise. And for this job, you will need a very big wrench in order to get leverage.

But on some newer BMW engines, you don’t have to remove this bolt since this balancer is attached with different bolts that are around this big bolt.

On FWD models, removing this harmonic balancer is a lot easier since you don’t have a radiator. The bolt can be accessed from below or from the fender side. Still, this bolt is also torqued pretty high, and removing it can be a real pain.

More on the procedure of how this harmonic balancer is replaced on BMW, you can check in the video that we attached.

Cost of Harmonic Balancer Replacement

The cost of replacing a harmonic balancer can really depend on the engine type and the engine layout. Usually, prices go between $150 and $550.

This is the case because in FWD engines, removing this component is really straightforward and can be done pretty cheaply with only an hour or two in labor.

While in RWD applications, the radiator has to come off and this will require draining the coolant and taking a lot more time for the same job. Resulting in higher prices.

While you do this job, we would also recommend that you replace the serpentine belt, idler, and tensioner pulleys. Just in case something breaks down, you don’t have to pay for the same stuff all over again.


The harmonic balancer wobble can be a very annoying problem to deal with. But it can happen and the only way around is to replace the balancer with a new unit.

Symptoms associated with this problem as we noted are the wobble and squeaking sounds that can develop. But what is good is that it is not that very expensive to get this component replaced on your car. And if you are familiar with mechanics and want to wrench on cars you can even pull this off by yourself.

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