What can be a sign that engine mounts are failing?

Excessive vibrations and noise can indicate that engine mounts are failing. Engine mounts are designed to secure the engine to the vehicle's frame while dampening the vibrations produced by the engine's operation. When these mounts begin to deteriorate or break down, they can no longer effectively absorb these vibrations, resulting in more noticeable shaking or harshness felt within the cabin and potentially leading to increased noise levels. This can also lead to misalignment of the engine, which may cause further mechanical issues over time.

The other options, such as improved engine performance, better fuel economy, and a smoother ride, would not typically result from failing engine mounts. Instead, those outcomes are associated with well-functioning engine mounts and other components of the vehicle working effectively.