Nobody wants to be left with an expensive repair bill, but getting problems fixed as soon as they happen can save you lots of time, money and stress in the long run. That’s why it’s important not to ignore rattling noises (even if you really want to!).

This guide will take you through the most common causes of rattling, so you can decide whether to tackle the problem yourself or leave it to a mechanic.

Guide Contents:

What does it mean if my car makes a rattling noise?

Rattling noise under my car

Rattling noise under my car bonnet

Rattling noise while accelerating

Rattling noise from inside car

What does it mean if my car makes a rattling noise?

If your car is making an unusual rattling noise, there could be a number of causes. In most cases, it will have something to do with a loose part or component. The easiest way to work out what could be causing the noise is to pinpoint which area of the car it's coming from.

Rattling noise under my car

Loose exhaust system

If you hear rattling from under the back end of your car, it’s a sign that the exhaust system has become misaligned. Alternatively, the muffler, which is positioned right by the tail pipe, could have come loose. Fortunately, both of these problems can easily be fixed and shouldn’t cost you too much money.

Faulty suspension

Particularly if you hear rattling while going over potholes or speed bumps, it’s likely your suspension is at fault. Issues could come from one of the many components of the suspension system, including control arms, ball joints, tie rods, strut mounts or the sway bar link. The best course of action is to take your car to a garage to have the suspension system checked by a professional.

Rattling noise under my car bonnet

Low engine oil

The first thing to check if you can hear a rattling noise under your car’s bonnet is the engine oil level. If there isn’t enough oil circulating through your engine, it can cause rattling as different parts rub together without enough lubrication. Top up your oil as needed to avoid causing serious damage.

Cracked or broken serpentine belt

The serpentine belt drives your car’s alternator, AC compressor and water pump. If you’re not sure how to tell the difference between a serpentine belt and a timing belt, the latter can’t usually be seen because it’s hidden under protective covers. 

If you drive your car with a faulty or broken timing belt, the engine will overheat, so the best thing you can do is open up the bonnet to have a look and decide whether you can take the car to a mechanic yourself or if it will need towing.

Rattling noise when accelerating

Broken catalytic converter

Your catalytic converter consists of small, honeycomb-shaped pieces that can cause a rattling noise when broken. If this is the case, the rattling will be loudest when you start the engine and will get worse over time. Unfortunately, catalytic converters can be expensive to replace, but this isn’t a job that can be put off.

Rattling noise inside car

The good news is that any interior rattling is likely down to something small and can probably be fixed by you. Check the interior for any objects that are loose and could be causing the rattling. The glove box is a good place to start. You should also check the in-door storage pockets. If you can’t find an obvious source of the noise, you might need to take your car to a garage where they can look for any underlying causes.