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Car Squealing When Accelerating? (Reasons & Solutions)

A fine-tune, well-maintained car will drive smooth like butter. But when you try modifying the engine without any preliminary experience or ignore the basic maintenance, then you most certainly have to deal with a bunch of problems.

Squealing noise while accelerating is a great red flag. Let’s find out what could be the most probable cause behind it. 

Why is my car squealing when I accelerate?

The squealing noise might be caused by a worn or damaged belt. In most cases, the obnoxious sound will be produced by the serpentine belt. Its various operating functions and continual strain render it susceptible to tiny raptures. A worn-out serpentine belt may cause the engine to overheat.

Any squealing noise coming from the car hood might be irritating and the possibility of engine damage and repair may be a headache for some.

If the noise is identical to metal colliding, we can assume that there is a problem with internal parts, although squealing noises are usually caused by defective rubber belts.

Rubber belt has gone bad:

Depending on the type and model of your car, you may have a serpentine belt or a V-belt.

If you have a serpentine belt, it will take less time to identify any rupture or dryness in the belt, however, a V-belt installation will require you to inspect several belts for faults.

The squealing noise will be created mostly by dry or worn-out belts, regardless of the installation.

The constant exposure to heat, faulty or misalignment of the idler pulley, also a worn-out pulley bearing could be the reason behind the damaged condition of the belt.

Misaligned installation:

If you prefer to work on your own vehicle, do repair, restoration and installations then you should take a good look at the device alignment.

If you are getting squealing noise out of your car after a new device installation, there is a high chance that the tensioner or the idler pulley is out of its regular alignment.

Any non-aligned parts can create a huge amount of strain in the belt which leads to major damages hence the squealing noise.

Leaking oils or coolant:

The rubber belt in contact with coolant or any oils will start to lose its efficiency. Even a new serpentine or V-belt could become completely unusable if it continuously gets in contact with coolant.

What Are Serpentine And V-Belts?

As for the different parts of the car, serpentine belt and v-belts are two prominent parts of the whole. Let’s get to know them.

Serpentine belt:

Just like the name suggests, a serpentine belt is a long continuous belt attached to several mechanical parts of the engine and the connection layout of the belt is somewhat similar to a snake’s movement. 

It’s a heavy-duty belt capable of delivering ample amounts of power to run devices like alternator, air and water pump, air compressor, and power steering.

The serpentine belt is usually attached to a hydraulic tensioner which helps it guide through and also it gives the belts its peculiar serpentine shape. Sometimes an idler pulley will replace the tensioner.

For a serpentine belt, carrying massive amounts of load while being in constant tension requires a poly-v construction.

The best thing about a serpentine belt is that one belt is enough to efficiently deliver the required power to several mechanical parts, you won’t have to deal with multiple belts systems anymore.

The serpentine belt helps the engine to be in a compact and dynamic shape, increasing performance. Another advantage of the serpentine belt would be the less chance of flipping over, and easy to replace system. 


It’s a rubber belt looped around rotating shafts and the placement layout imitates the shape of V.

The V-belt acquires more space to function compared to the serpentine belt, also the V-belt is designed to transmit power to a singular mechanical device where the serpentine belt is made to work on multiple.

It’s no wonder that the serpentine belt is replacing the V-belt. However, simple installation, wide availability in the marketplace, and being cheap to use still make the V-belt a reliable choice.

How do you know if your serpentine belt is bad and causing the squealing?

As the main purpose of the serpentine belt is to transmit power to several mechanical devices, even a small defect in the belt will put a negative impact on the performance of the engine.

Here are some easy ways to detect if there is any problem with the serpentine belt.

Squealing noise:

Dry and worn-out serpentine belts will always produce quilling noises.

An easy way to confirm your doubt about the source of squealing noise would be to open up your car’s hood and pour some water or any kind of lubricant onto the serpentine belt, if the noise goes away that means the belt has lost its effectiveness and became dry and brittle.

It would be highly advised not to believe that applying water on the belt is the solution for squealing noise, a worn-out dry belt should be immediately replaced with a new one. 

Issues with multiple devices:

As the serpentine belt transmits power to devices like air and water pump, compressor and alternator, power steering; If the belt is worn out these devices will surely show a drastic decrease in performance.

You are most likely to face stiff power steering or an unresponsive air conditioner. 

Engine efficiency decreases: 

If you ignore all the minor symptoms and carry on driving with a bad serpentine belt, you may have to pay a hefty price for your ignorance.

In the worst-case scenario, you may have to deal with issues like engine overheating or complete shutdown. Once an engine goes through shutdown it’s almost impossible to get back to its original efficiency.

Is it safe to drive with a worn serpentine belt?

No, it’s not safe to drive a vehicle with a worn serpentine belt. Doing so could damage the attached devices like the alternator, power steering, compressor, and more.

A worn-out serpentine belt won’t be able to provide the required power to the idler pulley hence the performance efficiency of the engine would be compromised.

If you drive a vehicle with a worn serpentine belt the internal damage to the essential parts could be beyond repairs.

Can you drive with a broken serpentine belt?

Driving with a broken belt is a very dangerous decision and you should never do it. The serpentine belt is responsible for several important functions of your car.

If you drive with a broken serpentine belt, you might lose control over the steering or it may become too stiff to handle.

Driving with a broken serpentine belt means compromising your vehicle’s alternator which controls all the electrical functions of your vehicle.

And the worst thing about driving with a broken serpentine belt is the effect on the engine cooling system. The engine is sure to overheat and may result in permanent damage. 

However, if your serpentine belt gets broken while you are driving or you have ended up in the middle of nowhere then you can drive a maximum of 45 minutes.

You should turn off electronic features like your radio, Air conditioner if possible the lights to reduce the electrical load on the battery. Driving for a short amount of time may not cause that much damage to the engine but it’s only advisable in drastic situations.

How often to replace a serpentine belt?

Generally, a serpentine belt can last very long, however, the built quality and maintenance will play an important factor in determining its service period. You can easily reach 40,000 to 50,000 miles without any worries.

It would be wise to change the serpentine belt when you traveled 80,000 miles. That being said, you should always keep an eye on the condition of the belt.

There are more than a few ways for the belt to lose its efficiency, so it’s better to replace it if you find any minor rapture or brittleness.

How much does it cost to replace a serpentine belt?

The price range of the serpentine belt is around $30 to $80 and the installation bill is usually $80 to $100. However, you can save a big amount of cash just by learning the basics and installing the belt on your own.

That being said, it’s better to seek professional help if you are frequently facing problems with your serpentine belt. Most likely the alignment of the idler pulley or tensioner is a bit off.

Final thoughts

Power steering, alternators, air, and water pumps, and other components will all play an active role in the acceleration process, and they are usually linked by a serpentine or V-belt. Continuous strain and weather conditions might destroy the rubber belt, resulting in squealing sounds.