New Jersey Air Brakes Practice Test

A common indication of a failing air compressor is the presence of unusual noises during operation. These noises may include grinding, rattling, or hissing sounds, which can signal mechanical issues, such as bearing wear, damaged internal components, or air leaks. Such auditory signs alert the driver to potential problems that could affect the performance of the air brake system.

In contrast, increased air pressure may suggest that the compressor is functioning well, as it is effectively building up pressure as needed. Fluctuating brake pressure can indicate issues with the brake system or its components, but may not directly reflect the performance of the air compressor itself. Complete air loss is a serious condition often resulting from significant failures within the system but might not be strictly indicative of compressor failure, as it could also be due to leaks or other problems in the air brake system. Hence, unusual noises serve as an important early warning sign of compressor deterioration.