What is a ‘good car sound’? Can you tell when your car sounds unhealthy?

Car sounds good – music to the ears; car sounds bad – scraping, grinding, knocking, tapping or squealing are some of sounds you hear when something is wrong. This article aims to help you tune into the sounds your car makes when its healthy and running well and sounds you should not ignore when something is wrong. If there’s a fault with your car the symptom is often an unusual noise; a noise you should not ignore.

This article also aims to give you more information to help you to decide if you can tackle a job yourself or should you get specialist, expert help. Knowledge is power. Find a good garage/mechanic you can go to if the job is too much to do yourself; and you’ll get more respect if you know something about the problem.

When an engine is running properly it has a healthy sound. The healthy sound is a regular, constant note. Like music with a regular, unchanging rhythm a healthy engine running at a constant regular speed will not hunt and wander and there won’t be any extra noises. Also the engine will pick-up and run smoothly and powerfully when you apply the accelerator pedal.

Unhealthy engine noises include valve train noises(clicking or tapping), sticky hydraulic tappets (knocking), etc. Usually these will be metallic sounding. Scraping, grinding, knocking, tapping or squealing are some of sounds something is wrong

Unhealthy hissing noises from the engine bay may well be the result of a coolant leak somewhere. Coolant/anti-freeze flows in the engine and in pipes or tubes. These can develop small holes or come loose where they are joined. Never ignore coolant leaks or noises. Always check out immediately. Low coolant level can easily mean an engine seizing because it gets too hot. Seizure is bad news for your budget. Very expensive repair bills are almost always the result. If you hear a hissing noise or see fluid leaking onto the floor beneath your car check under the bonnet/hood to find out, if possible where it’s coming from. Keep an eye on the dashboard temperature gauge; there will be a change in temperature if the coolant level gets low.

Noises coming from the wheels on your car will usually mean either wheel bearing problems or brake problems.

Wheel bearings are the sort of job you can tackle for yourself and save money. If you need to replace bearings shop around for a good price and also for good quality. Wheel bearings on today’s car are usually Taper bearings. This means they can be adjusted to ‘take up’ normal wear and tear. Usually good quality bearings will last a considerable time and do a fair number of miles. Normal wear and tear can be dealt with by tightening the retaining nut. Make sure you adjust them correctly; too tight and rapid wear and over-heating will result, too loose and rapid wear will also occur.

Noises from the wheels on your car will most likely be from the brakes if the bearings are OK. Brake noises are usually caused by excessively worn brake pads (grinding, scraping noise) sticking caliper piston, excessively worn brake discs. Squealing from the brakes is not always a sign of danger but don’t ignore it. Consult an expert if you’re not sure.

Brakes on modern cars are not rocket-science. but need to be maintained for the obvious reason of safety. Replacing brake pads is a job you can tackle yourself and save money on mechanics bills. You will find plenty of more detailed guidance on the net or in a Haynes manual for your specific car. Brakes can bind (not release properly), caliper pistons can seize, and worn brake pads can mean metal is running on metal.

The design of some brakes means they can sometimes squeak….open the window while driving so the noise is audible, when safe to do so lightly touch the brake pedal so the brakes are applied lightly. if the noise goes away you can be more confident it is something to do with the brakes.

Modern car brakes have a long history of design and modification behind them. All modern brakes are hydraulically operated. When you press the brake pedal a brake caliper squeezes two pads together and the brake disc sandwiched between them is slowed down. The wheel is slowed because the wheel and disc are attached to each other. The pads have a brake lining glued to them and this lining wears sometimes so thin that the metal backing of the pad makes contact with the metal brake disc. Preferably don’t let them get this bad. Take a look at the pads – you can see how much lining is left on them.

The engine has a lot of moving parts and can produce a lot of noises. Listen to the engine when it’s healthy and unhealthy noises will be easier to recognise when they occur. Oil is the lifeblood of an engine; it reduces friction and heat. Low oil level will generally mean the engine sounding harsher. Noises from top or bottom of the engine may indicate bearing or component problems. When it’s healthy try to keep it that way with regular oil and filter changes; you can do them yourself!

Lastly pay attention to the noises that seem to be coming from the exhaust. The exhaust pipe and the silencers/mufflers are under the car and exposed to water, salt (winter) and very high temperatures (exhaust flame temperature around 1000 degrees C) The exhaust is heated and cooled frequently so it will develop leaks eventually. Any leaks from the exhaust are also a health/safety issue because of the danger of carbon monoxide. If you suspect it get it checked at an exhaust repairers; genuine firms will tell you true and not usually charge for diagnosing a problem.