Similar to running rich, the MAF sensor is sending inaccurate information to the PCM. “Running lean” - the opposite of running rich - means your vehicle has too little fuel and too much air in each combustion chamber. Most of the time, the problem can be fixed by cleaning the MAF sensor's wires. When it overestimates the airflow, the PCM releases too much fuel. It can't measure airflow accurately, therefore sending incorrect information to the PCM. These issues can happen when the MAF sensor is damaged or when its wires are coated with dirt. Signs that your vehicle is running rich include: “Running rich”means there is too much fuel and not enough air in each combustion cylinder. If you experience any of these symptoms you should examine your vehicle as soon as possible. These issues can create dangerous situations causing accidents and injury. This could happen while speeding up on the highway on-ramp or cruising down a city street. You’ll experience this as poor drivability such as hesitations or sudden jerking motions, particularly during acceleration. Stalling, jerking, or hesitation during accelerationĪ bad MAF sensor can cause too much fuel to be left in the combustion chamber, creating untimed detonations. There are 3 key signs that may indicate it’s time to examine your MAF sensor. This causes the engine computer to miscalculate the amount of injected fuel, causing additional damage to your engine.

A contaminated or failed mass air flow sensor cannot measure the amount of air flow correctly.

The mass air flow (MAF) sensor, part of your vehicle’s electronic fuel injection system, is responsible for calculating the total amount of air entering the engine.

Mazda 3 mass air flow sensor problems