What is the result of filter restriction in diesel engine air filters?

Filter restriction in diesel engine air filters directly impacts the engine's performance and longevity. When an air filter becomes restricted, it cannot allow adequate airflow into the engine. This insufficient airflow can lead to a phenomenon known as "engine breathing" issues.

As a result of this restriction, the engine may struggle to receive the necessary air to properly mix with the fuel during combustion. This imbalance can lead to incomplete combustion, increased exhaust emissions, and can ultimately cause increased wear and tear on engine components. The engine may have to work harder to draw air, which increases stress on various parts, including the turbocharger and the intake system. This wear can result in premature failure of engine components, making it crucial to maintain clean air filters for optimal performance and longevity.

The other responses describe outcomes that would not arise from filter restriction: higher fuel consumption does result from inadequate air supply, but it is a secondary issue; better airflow and improved efficiency are directly negated by filter restriction.