The only sound you should hear is the soft purr of your car’s engine—and occasional loud music when your favorite song comes on. If you’re hearing another noise from under the hood (or in the wheel wells or…), don’t turn up your radio or ignore it. That noise could mean a serious problem that could leave you stranded. While we can’t give you an exact diagnosis until you bring your car in, we can give you an idea of what is causing that sound—and why you shouldn’t ignore it.
Possible cause: The serpentine belt keeps the AC, power steering pump, and other vital parts of your car functioning. A worn serpentine belt can let out a squealing sound when it’s time for replacement. If you wait too long, a broken serpentine belt can leave you stranded.
Possible cause: Wet or worn brake pads can let out a squeal. When the squealing doesn’t stop or is accompanied by vibrations, a pull to the left or right, and a soft pedal, schedule an appointment with a mechanic to get new brakes—and a safer feel when you press the brake pedal.
Possible cause: A power steering pump is part of the system that allows you to turn the steering wheel easily. When it feels like turning is a harder task or if the car is squealing when the car starts, the power steering pump could be the culprit. As soon as you can, contact a mechanic about checking the pump and power steering fluid level.
Possible cause: An alternator recharges the car’s battery while the car is running and provides power to key car parts (i.e. headlights, starter, dashboard lights). When the alternator bearings are worn, they can let out a squeal that needs to be addressed by a mechanic as soon as possible.
Possible cause: Brake pads with no pad left can let out a grinding sound when metal contacts metal. If you even suspect this is the problem, get the car to a mechanic immediately to replace the brakes.
Possible cause: Wheel bearings allow the tires to spin with little or no friction. Wheel bearings can last for more than 75,000 miles (even up to 150,000 miles), but they do wear out eventually and emit a grinding sound when they need to be replaced. Other signs of a worn wheel bearing are a vibration in the steering wheel and abnormal tire wear.
Rough starting noise
Possible cause: A car battery is one of the primary sources of power, which is why a car with a failing car battery has problems with starting. If your car is making a rough starting noise or the battery goes dead periodically, get the car in to the mechanic quickly for a new battery.
Possible cause: Spark plugs provide the spark that starts your engine. Over time, the gap at the top of the spark plug widens, impacting the spark and causing a slow start. Weak spark plugs can damage other parts of the car and cause the engine to misfire. Spark plugs can last anywhere between 30-100,000 miles; schedule an appointment to get those spark plugs replaced before they cause more damage or completely fail.
Possible cause: An alternator is another key part of your car’s electrical system. Typically, you can tell when it’s time to schedule an appointment for alternator replacement when the car is slow to start, makes a rough starting noise, the battery dies, or the headlights or dash lights start to dim.
Possible cause: Tire alignment is a matter of geometry; your car’s wheels leave the factory with optimal angles that can be altered (negatively) by pot holes and bumpy roads. In addition to shaking and rattling, cars out of alignment may also pull to the right or left or drive with a steering wheel that is not straight. If you suspect it’s time for an alignment, don’t wait to get your car into a shop with the right equipment for a full alignment. If you keep driving a misaligned car, you may have to pay more for replacing suspension parts and tires over the life of the car.
Possible cause: You car’s exhaust system is essential to the health of your car; it’s also an essential part of passing your next emission test. When parts of the exhaust are loose, they can cause a rattling sound that needs to be addressed by a mechanic.
Possible cause: Worn brakes let you know in a number of ways that it’s time for replacement (i.e. soft brake pedal, pull to the left or right). When your car starts shaking and rattling, it’s a sign that there is little (if any) metal left on the rotors and pads. Make an appointment with your mechanic before you have issues with stopping on your next commute or road trip.