6 car sounds you should not ignore

Don't just turn up the music and tune out the noise. If you car is emitting these screeches, howls, and groans, then it needs some attention right now.

1. A Diesel-Like Clattering in Your Gas-Powered Car.

Worst-Case Scenario: Detonation, also known as pinging or knock.
Why: Things like bad gasoline or incorrect ignition timing cause the fuel to go boom too early. If left unchecked, you risk serious engine damage.

What To Do: Switch to higher octane gas, which resists detonation, and check the timing.

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2. Questlove Drumming Underneath Your Car when It's Moving, Increasing with Vehicle (Not Engine) Speed.

Worst-Case Scenario: Failing universal joint or driveshaft bushing.
Bad Stuff That Can Happen: U-joint fails completely, driveshaft digs into pavement, and the car pole-vaults and crashes.
Why: Both the U-joint and bushings simply wear out. The noise comes from the driveshaft flopping around like an ailing fish.

What To Do: Inspect the driveshaft for worn or broken parts, replace them, or get to a mechanic.

s3. A Million Fingernails Scraping on a Chalkboard when You Start Up the Engine or Accelerate from a Stop.

Worst-Case Scenario: Loose accessory drive belt.
Bad Stuff That Can Happen: Your enraged neighbors will kill you.
Why: The belt is slipping on the pulleys, either due to age and wear, or improper tension.

What To Do: Inspect the belt for minor cracks or fraying. Replace as needed.

4. Sharp Tapping Like a Clunky Washing Machine, Increasing with Engine RPM.

Worst-Case Scenario: Connecting-rod knock.
Bad Stuff That Can Happen: Broken rod blasts hole through the engine block; metal parts and flaming oil shoot out.
Why: Usually a failure of a rod bearing due to oil starvation.

What To Do: Stop driving immediately. If caught early, the bearing can be replaced.

5. Grinding Metal—Think Snowplow on Pavement.

Worst-Case Scenario: Brake pad or shoe material completely gone.
Bad Stuff That Can Happen: Destroyed brake rotors or drums. Car may pull to one side under braking and possibly crash.
Why: Brake pads should make a squeal when the pad has worn down to the danger zone. But sometimes we don't notice this sound.

What To Do: Fix the brakes.

6. A Whine Like an Empty Ice Machine When You Turn the Steering Wheel, Especially at Low Speed.

Worst-Case Scenario: Failing power-steering pump.
Bad Stuff That Can Happen: Loss of steering assistance.
Why: Low power-steering fluid or a pump groaning to death.

What To Do: Check the fluid level, top off as needed, and get ready to buy a new pump.

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