From a low spooky grumble to a shrill chirp, a lot of automobile noises can sound like a monster has taken up residence in your engine block. But it's no ghost or ghoul — the sounds coming from your vehicle can be a warning sign of needed repairs. Keep an ear our on your next drive for things that go bump under the hood:

Metallic grinding: If you notice a metal-on-metal crunch or squeal when braking, it's possible your brake pads are shot. The sound usually means your brake shoes are grinding into and damaging the rotors.

Roaring or low humming: It could be a stretch of rough asphalt, but worn-out tires or under-inflated tires can also create a deep hum, particularly when traveling at high speeds.

Squealing: A brittle or slipping serpentine belt could be behind the squealing noises coming from your engine. Don't ignore this one — taking care of serpentine belt problems before it snaps or falls off can save you hundreds of dollars in repair costs.

Hissing: A hissing sound usually indicates a leak or improper seal. The usual culprits are from a coolant system or vacuum line.

ClingClanger, available on the web and as a smartphone app, provides short audio clips so you can compare what you hear in your own car with the sound of known engine issues. Of course, nothing substitutes for the expertise of a trusted mechanic, but with just a little listening, you can get an idea of what your car is trying to tell you.