Most drivers think they know what their car sounds like when something goes wrong. But a new study suggests that confidence can be costly.

Autotrader surveyed 2,000 drivers and found that ignoring strange car sounds leads to an average of $540 in extra repair costs. That’s the price many pay for misjudging or delaying service. And despite how confident people feel about their diagnostic skills, most of them get it wrong.

The study played real car noises and asked participants to identify the problem

Over 70% of drivers misdiagnosed at least half of them.

The most commonly misjudged issues were low power steering fluid and bad wheel bearings. More than 80% got those wrong.

Even the “unmistakable” sound of a seized engine fooled nearly three-quarters of drivers. 

On the other hand, drivers did a little better spotting worn brake pads, with just under half identifying that correctly.

Drivers who ignored early warning signs often paid the price

One in three admitted to putting off a repair, and one in five said that decision eventually cost them over $900. 

Men were more likely than women to wait before getting help. Nearly half of men said they delayed fixing a known issue. 19% of women did the same.

Car brand loyalty seemed to play a role in confidence

Mercedes-Benz owners were the most self-assured, but BMW drivers performed best on the actual test, identifying eight out of ten problems correctly. Chevrolet owners ranked near the bottom. They were also the least likely to take their car in right away after hearing a strange sound.

How drivers respond to car trouble varies. Some head straight to the mechanic, while others wait days or even weeks. Younger drivers often turn to friends or the internet. Older drivers tend to do more research before deciding.

I listened to the test sounds

The study summary page has sound bites of car problems. Now, I worked as a service advisor at a car repair facility for many years.

I’ll be the first to say that just being given audio clips of something humming or banging is a real challenge.

The truth is, while guessing is a fun activity, I’ve learned that even the most seasoned mechanic relies on more than their ears. Sight, smell, touch, and tools are really what it takes to properly diagnose a car problem.

Trust your ears, but also trust a pro

Misdiagnosing an issue or waiting too long can snowball into a much more expensive fix. If your car starts making a new sound, it’s better to get it checked before that squeak or rattle turns into a full-blown repair bill.