What is a potential consequence of failing to replace a clogged air filter?

A clogged air filter restricts the flow of air into the engine, which is essential for the proper combustion of fuel. When airflow is decreased, the engine cannot achieve the optimal air-fuel mixture necessary for efficient operation. This may lead to poor engine performance, reduced acceleration, and increased engine wear over time. Additionally, because the engine cannot breathe properly due to the inadequate intake of air, it may struggle to produce power effectively.

In contrast, the other choices don't correlate with the consequences of a clogged air filter. Increased fuel efficiency would not occur since a lack of proper airflow can lead to inefficient combustion, thus decreasing fuel efficiency instead. Improved engine performance is typically dependent on the air filter being clean and functioning, so a clogged filter would hinder rather than enhance performance. Lastly, reduced emissions would likewise not be the result of a clogged air filter, as improper combustion often leads to incomplete fuel burning, which can actually increase harmful emissions.