Which is a sign of a failing brake system?

A long stopping distance is a key indicator of a failing brake system. When brakes begin to wear out, they lose effectiveness, resulting in the vehicle requiring more distance to come to a complete stop. This can occur due to factors such as worn brake pads, leaks in the brake lines, or issues with the brake fluid. Drivers should be particularly attentive to changes in how responsive their brakes feel; an increase in stopping distance can signify that maintenance or repairs are necessary to ensure safety.

The other options relate to different vehicle systems. Noise during acceleration typically points to issues in the drivetrain or engine components. An engine misfire indicates a problem with the engine's combustion process, which could be caused by faulty spark plugs or fuel delivery issues. Fluctuating fuel efficiency often signals problems related to fuel injectors, air filters, or even tire pressure. Understanding these distinctions helps drivers identify the specific areas of concern in their vehicles.