What is a common symptom of a malfunctioning mass air flow (MAF) sensor?

A malfunctioning mass airflow (MAF) sensor can lead to various issues with engine performance, notably poor fuel economy and engine stalling. The MAF sensor measures the amount of air entering the engine, which is critical for determining the correct fuel-to-air mixture. When the MAF sensor is faulty, it can provide inaccurate readings, causing the engine control unit (ECU) to miscalculate the amount of fuel needed. This imbalance can result in too much or too little fuel being injected, leading to poor fuel economy as the engine struggles to operate efficiently.

Additionally, an incorrect air-fuel mixture can cause the engine to run too lean or too rich, which can lead to stalling when the engine cannot maintain proper operation under load or during idle. This symptom, therefore, clearly indicates a malfunctioning MAF sensor, as it directly affects both fuel efficiency and engine stability.

The other options mention symptoms that are typically associated with different issues. For instance, sudden acceleration can suggest problems with the throttle or transmission, excessive exhaust smoke often indicates engine issues such as oil burning or a failing catalytic converter, and transmission slipping is related more to transmission problems rather than engine airflow or fuel management. Hence, the association of poor fuel economy and engine stalling directly