MAF Sensor Failure: The Main Signs and Symptoms
The Mass Air Flow Sensor (or MAF sensor) is a critical engine component that detects how much air enters your car's engine. When it works well, the MAF sensor should send out signals to a specialized computer in your car known as the Engine Control Unit (ECU). The ECU uses the information from the MAF sensor to release the right amount of gas necessary for engine combustion.
Both these components work together to ensure the proper function of your car's engine. Oftentimes, a bad MAF sensor will greatly affect your engine's performance, so be sure to watch out for any of the following signs of failure.
1. The Engine Runs Rich or Lean
When your car's engine runs rich or lean, you have an imbalance of the air-fuel mixture in the combustion chamber. Either of these cases can turn on the check engine light on your dashboard.
If the engine runs rich, the combustion chambers have more fuel than air in the cylinders. This problem happens when the MAF sensor registers incorrect air volume levels and sends out the wrong data to the ECU. The ECU then lets out excess fuel into the combustion chambers.
Your car engine may run rich if you can identify any of the following symptoms:
- Deep black smoke from the tailpipe
- Poor fuel efficiency
- Rough idling
Conversely, if the engine runs lean, the combustion chamber has more air than fuel. Here, the MAF sensor doesn't detect the right airflow levels and sends out inaccurate signals to the ECU. The lower amount of fuel released into the combustion cylinders may give you better fuel efficiency. But your engine will suffer extensive damage in the long run.
You can look out for symptoms such as:
- A hard starting engine
- Hard engine seizures
- Frequent engine surges
Both these engine problems may occur if the MAF sensor is dirty or severely damaged. Let a qualified mechanic take a look so they can draft the right approach to get your vehicle back in order.
2. The Engine Has Hesitation and Jerking
A failing MAF sensor can trigger inconsistent detonations in your engine. You're likely to notice engine hesitation whenever you try to drive faster. You may also experience sudden forward jerking, a problem that can put you in harm's way. Uncontrolled jerking on a freeway or a busy street can cause unexpected collisions with other vehicles ahead.
For proper acceleration, more air should flow into the engine, a step that triggers the ECU to release more fuel into the mixture. The ECU calculates the right amount of fuel based on information from the MAF sensor to give your engine the right push.
However, a bad MAF sensor will give off inaccurate airflow values, and the ECU may not release the right amount of fuel to match the force on the gas pedal. Your car might seem to accelerate unevenly if an imbalance in the air-fuel ratio exists.
3. The Engine Is Stalled or Misfiring
Sometimes, your engine may start normally but suddenly stall when your car starts moving. You'd often have to crank the engine again after you experience this problem.
The engine could also misfire if the air-fuel mixture isn't sufficient enough for combustion. This problem may be due to a faulty MAF sensor that sends out inaccurate values to the car computer. If your vehicle stalls severally or misfires, talk to your mechanic about it as quickly as you can.
Don't try to fix the engine by yourself if you have little knowledge of how it works. These symptoms can be from other problems such as a blocked catalytic converter or a vacuum leak. The wrong diagnosis creates more problems than it solves.
Instead, consult with qualified auto experts like
Letcher Bros Auto Repair who can eliminate all other possibilities and narrow down on a bad MAF sensor.
