What could be the effect of a faulty MAF sensor based on oxygen sensor readings?

A faulty Mass Air Flow (MAF) sensor can significantly impact the engine's performance by providing incorrect measurements of the amount of air entering the engine. This incorrect data can lead to an improper fuel-air mixture in the combustion process. When the engine control unit (ECU) receives inaccurate readings from the MAF sensor, it may not inject the correct amount of fuel to match the volume of air.

This imbalance can cause the engine to run either too rich (too much fuel) or too lean (too little fuel), which directly affects fuel efficiency, exhaust emissions, and overall engine performance. For example, a rich mixture may lead to increased levels of unburned fuel in the exhaust, while a lean mixture can result in higher combustion temperatures and potential engine damage.

In summary, the primary consequence of a malfunctioning MAF sensor is that it disturbs the intended fuel-air mixture, which is crucial for optimal engine operation and emissions control.