4 Reasons for Engine Squealing | Hanson Subaru of Olympia

Things that Cause Squealing Sound in Car's Engine - Subaru Service Questions in Olympia, WA

July 24, 2019

Children often whine more when they're tired and worn out. If you hear a whining noise from your car's engine, it may mean much the same thing: there's a component that's worn out. If these parts break or wear down entirely, they could cause damage, so hearing a whining sound means that it's time to schedule a service appointment.

At Hanson Subaru, we believe that you deserve to know important information about your Subaru; that's why we've put together information pages filled with things you should know, just like this one. Below, we list four possible reasons you may be hearing a squealing or whining sound from your engine.

A technician inspecting the engine of a vehicle.

4. Worn Alternator

In most modern vehicles, you'll find an alternator that's belt-driven. This alternator is an incredibly important component: not only does it recharge the battery in your Subaru, but it also powers the electrical system when your vehicle is on. Over time, and alternator can wear down. If it's the bearings in the alternator that have worn out, it may make a high-pitched squealing noise. This means that it's time to have the alternator replaced.

3. Worn Drive Belt

The alternator is powered by the drive belt. This belt also makes sure that various other engine components work as they should. Since the drive belt is made of rubber, it will wear down eventually. When it deteriorates, it will often make a squeaking or squealing noise, and this is a sign that it needs to be replaced soon.

2. Worn Pulley Bearings

If it's not a problem with the drive belt, the pulley bearings may be at fault. Damaged or worn pulley bearings may cause a whining noise as the pulleys spin. In cases like these, it's generally best to replace the pulley or pulleys entirely.

1. Worn Belt Tensioners

Belts are generally made from rubber, which means that they tend to lose some of their elasticity and stretch over time. In the past, the tension of these belts would have to be adjusted as part of regular service, but this isn't the case any more. Modern vehicles come with belt tensioners that perform this job automatically. However, a worn-out or damaged belt tensioner may cause the belts to become loose. If this is the case, replacing the belt tensioners is a quick way to get rid of the whining.