Blog Car Care Advice 10 Reasons Your Engine Squeals When Starting the Car (+ How to Fix)
Car Care Advice

10 Reasons Your Engine Squeals When Starting the Car (+ How to Fix)

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Picture this: It’s a peaceful morning. You turn on the ignition, and suddenly, your car breaks the silence with a high-pitched squeal

Well, it might be time to check out your serpentine belt or belt tensioner!

Explore the possible reasons why your engine might be squealing when starting your car and how you can fix it.

This Article Contains:

Let’s put those squeals to sleep! 

10 Reasons Why Your Engine Squeals When Starting Your Car

From bad spark plugs to drive belt tensioners, here are a few reasons why your engine might be squealing and their fixes:

1. Damaged Serpentine Belt

If your serpentine belt (drive belt or fan belt) is damaged or isn’t tight enough, you’ll hear a distinct squealing or screeching noise when the belt slips or rubs against the pulley. 

As most drive belts are made of rubber-like materials, they can crack from heat or get loose from being pulled excessively through the pulley system. This leads to a loud squealing noise when you start the car and might get louder as you accelerate. 

However, a failing belt doesn’t turn on the check engine light, so you should look out for other signs like:

If the belt is old, hard, or cracked, you should replace it with a new belt immediately. A bad pulley can also cause these sounds — that’s why getting a professional to diagnose the problem correctly is vital. 

2. Faulty Drive Belt Tensioner

A drive belt tensioner helps maintain the correct tension on your vehicle’s drive belt.

If the tensioner lets the belt get too loose, the belt might slip out of place or come off. Meanwhile, the serpentine belt could crack or break if it gets too tight. In such cases, you may notice a loud squealing noise, irregular belt wear, or the alternator might not work well due to reduced engine performance. 

You can either adjust the belt tension or replace the old tensioner. 

3. Bad Alternator Pulley

If your car’s alternator pulley is worn out, loose, or has a bad bearing, it can cause a squealing noise when you start the vehicle. You may also get a burning smell or a dash warning light indicating a fault with the charging system.

When that happens, you may need to replace the bearing, alternator, or pulley.

4. Faulty Spark Plugs

Spark plugs ignite the air-fuel mixture in an engine’s cylinders to power the vehicle.

However, over time, the plug might not produce enough electric current to properly ignite the fuel in your engine. In such cases, your car might start to squeal when you put it into gear and press the clutch. 

The easiest way is to take it to an auto repair expert and replace your plugs.

5. Worn-out Brake Pads

Most modern brake pads in disc brakes are designed to make a squealing noise once they wear out — indicating it’s time to get new ones. Squealing noise can also be caused when debris gets stuck between the brake pad and the disc. 

Modern cars have a dashboard light to warn you about the brake pads. 

If your brake pads have worn out, it’s best to replace them before they affect your discs. 

6. Power Steering Issues

A lot of issues within the power steering system can make your car squeal. This includes:

How do we fix these issues?
Refill if the power steering is low or replace it if it’s contaminated. Additionally, you should get professional help to diagnose and fix the problem correctly.

7. Bad Timing Belt

If you experience a squealing sound when accelerating, a ticking noise from the engine, or engine misfires — a worn-out cambelt or timing belt is most likely the culprit. 

That’s because the timing belt can wear out or become loose over time. You should check how often your timing belts need replacing in your manual. Plus, keep an eye out for any tell-tale signs, as a bad timing belt can damage other expensive car parts.

8. Faulty Water Pump Pulley

Sometimes, you might misdiagnose the squealing sound as an alternator or cambelt issue when the actual culprit is your water pump pulley. 

The water pump pulley drives the water pump and helps circulate coolant through the engine to maintain optimal operating temperature. The bearings on the water pump pulley can go bad and make a squealing sound. And if you don’t fix the issue, it can overheat your engine. 

9. Low Levels of Antifreeze 

Antifreeze, a mixture of ethylene glycol and water, helps lower the freezing point of the coolant and prevents engine overheating. 

Low antifreeze levels can result in the crystallization of water in the remaining coolant. This can exacerbate corrosion in your engine cooling system — making your engine squeal. 

Why does this happen?
That’s because antifreeze also prevents corrosion and buildup of deposits. So, it’s important to top off your antifreeze levels to maintain top-notch engine performance.  

10. Worn-out or Under-inflated Tires

Do your tires squeal?
Well, your tires may be incorrectly inflated, worn out, or misaligned.   

Along with a squealing noise, if your car keeps pulling towards a particular side despite you holding the steering wheel straight, you may have a tire misalignment. Underinflated tires can cause a squealing noise, especially when turning. 

To avoid such issues, you should regularly take your car for maintenance and check your tire pressure every 2-3 weeks. If you feel you’re frequently inflating your tires, it might be time for a new one.  

So, can you drive with your engine squealing?
Let’s find out.

Is it Safe to Drive with a Squealing Sound?

No, driving with a squealing noise isn’t safe as it could signal dangerous issues. 

Here are a few risks you might face if you keep driving with a squealing noise:

So, it’s recommended to schedule an appointment with a mechanic ASAP for a thorough diagnosis and necessary repairs to ensure safety. 

Next, let’s find out how much the fixing will cost you.

How Much Does it Cost to Fix Your Car’s Squealing Noise?

The replacement costs depend on your vehicle model, diagnoses, and parts that need fixing.

Here are some replacement estimates:

Enjoy a Quiet Ride with AutoNation Mobile Service

Your engine can squeal for various reasons, from bad serpentine belts and spark plugs to low antifreeze levels. And zeroing in on the correct issue on your own can be challenging. That’s why you have experts like AutoNation Mobile Service to help diagnose and fix your car. 

We’re a mobile auto repair service available seven days a week. We offer upfront pricing, convenient online booking, and a 12-month, 12,000-mile repair warranty.

All you need to do is contact us, and we’ll fix it for you in your driveway.