Ever had your car make an impromptu loud noise while you were driving along? The sound could be screeching or squealing, but the main thing about it is that it would be really annoying. The first thing you would want to know is where the noise was coming from, and what it means for the car. Following are explanations for the different noises your car might make.

Squealing or Screeching

This noise happens when there is too much pressure being applied on the brakes. The cause of this may be worn-out brake pads, or metal rubbing against metal. There are cases where the manufacturer installs a brake wear indicator, and it may be making the squealing sound when your brake pad needs a replacement. The bottom line is, you probably need new brake pads or brake rotors installed. This could set you back somewhere from $150 to $400, based on the model of the car and the extent of the damage.

Sizzling or Hissing from under the Hood

If you encounter this kind of sound when the engine is shut off, this signifies a possible leak. There may be oil or coolant leaking into a heated part of the engine, and maybe the engine is also overheating. You may need an oil change after this.


The engine may backfire when you are driving, causing a loud bang. If the mix of air and fuel is too rich, this can happen. There are other reasons as well, such as the need for a new catalytic converter, the camshaft timing belt having slipped, the ignition timing needing to be adjusted, or the spark plugs being connected to the wrong wire.

Growling or Humming

In these cases, it is usually a problem with the tires. The car starts making these noises when you need a replacement for the wheel bearings or even the tires. To find out which it is, move the wheel to the front and back a bit and to a side, and keep an ear out for the pitch of the noise. If there is a change in the pitch, but not when the car is going straight, then it means that the wheel bearings need changing.


These sounds usually come from under the car, and can mean one of many things. Maybe you need a lubricant, or the transmission you are using is about to fail. Just the sound is not enough to conclude as to what might be wrong. So get in touch with an auto repair technician to diagnose the problem and fix it before things get worse.