Although no vehicle can run without making at least some degree of noise, certain sounds can be an indication that it's time to schedule a visit to the repair shop. The following are five sounds that your car shouldn't be making and what they can tell you about its condition.
Hissing noises from under the hood could indicate a problem with your vehicle's heating system -- always check for the presence of steam if you hear this type of noise, and shut the engine off immediately if steam is part of the picture. The culprit in these cases is either a malfunctioning thermostat or problems with the engine that cause it to overheat. Check for a sickly-sweet odor -- that means that your engine is leaking coolant, which could very well cause it to overheat. To avoid the risk of burns, always take extreme caution when raising the hood when your vehicle is steaming and hissing -- open it slowly and be prepared to back away quickly if you are greeted with a thick cloud of steam. Do not attempt to add water to the radiator or coolant to the coolant reservoir until the engine has cooled completely.
Grinding When Hitting the Brakes
Grinding sounds produced as a result of stepping on your brakes is a sign that your vehicle needs to be seen by a qualified mechanic immediately. This is not the type of potential problem that can be left for later -- grinding sounds are an indication of metal-on-metal issues and serve as a strong signal that your brake pads are completely worn out. Continuing to operate a vehicle with brake pads that have worn through can result in expensive repairs as well as pose a serious safety risk when total brake failure occurs.
Squealing When Accelerating
This is usually an indication that your vehicle's fan belt has come loose or that it's reached the end of its life -- you can tell when a fan belt needs replacing because its surface will appear cracked and brittle. Fan belts that are simply lose or misaligned can be tightened or re-aligned. Fortunately, even though the sound can be loud and annoying, it's something your mechanic should be able to repair quickly or replace quickly.
Squealing When Braking
Squealing when braking isn't nearly as serious as hearing a grinding noise when you step on the brakes, but nonetheless, it's something that requires the attention of a mechanic. It could be as simple as debris or water on your brakes and may occur for a short period of time as a result of driving over standing water. Squealing brakes are also an indication that your brake pads may be beginning to experience wear -- if this is the case, now is a great time to replace them before more serious grinding noises come along to let you know that your vehicle's brake pads are worn completely through.
Ticking While Idling or Driving at a Lower Speed
If you hear a ticking noise coming from your car while it's idling or while you're driving at lower speeds, this could mean that your vehicle is low on oil. The ticking will be coming from the hydraulic valve lifter and indicates that it is not being properly lubricated. You should immediately check the oil level on your vehicle if you happen to hear this noise. If your car isn't low on oil or if adding more oil does not rectify the problem, it's time to make an appointment with your local mechanic in order to get to the bottom of the mystery noise.