What happens when a mass air flow sensor is dirty?

When a mass air flow (MAF) sensor is dirty, it can provide inaccurate readings of the air entering the engine, leading to an improper air-fuel mixture. This can result in poor engine performance, reduced fuel efficiency, rough idling, and increased emissions. In some cases, it may also trigger the check engine light. Regular cleaning or replacement of the MAF sensor can help maintain optimal engine performance.