The mass airflow (MAF) sensor and the engine control unit (ECU) work together to make sure that you always have enough air in the combustion chamber for engine combustion. If the MAF sensor goes bad, the amount of air in the chamber will be adjusted incorrectly. This is because the mass airflow sensor is sending the wrong information to the engine control unit. Scotty’s Automotive advises that you may never have to replace your MAF sensor, but if you notice any of the following signs of a bad mass airflow sensor, you may need to replace this auto part after all.
Acceleration Lag
If a misreading from the MAF sensor tricks the ECU into putting too much air into the combustion chamber, your vehicle’s acceleration will lag. This is because it has more air than fuel and, consequently, it is fuel-starved.
Bad Gas Mileage
If a misreading from the MAF sensor tricks the ECU into putting too much fuel into the combustion chamber, your gas mileage will tank – pardon the pun. When the engine has too much fuel, it burns off the excess that it doesn’t need.
Black Exhaust
This not only causes problems with your gas mileage but it also causes black exhaust to flow out of your tailpipe. The thicker the black exhaust smoke the more excess fuel your engine is burning and the more dangerous it is to continue to drive your car.
Check Engine Warning
The imbalance in the combustion chamber will cause the ECU to turn on the check engine light. Usually, when the MAF sensor fails, it also sends an error code to the ECU and this causes it to turn on the check engine light, as well.
Engine Hesitation
You will also notice engine performance problems if the mass airflow sensor is malfunctioning. In the case of a fuel-starved engine, the engine will not only hesitate when you accelerate but also as you try to pick up speed. Once you reach the desired speed, it may continue to stutter and struggle to run.
Engine Surging
When excess fuel is the problem, you will feel as if you are driving a bucking bronco. The engine will surge forward because it will pick up speed even though you keep your foot’s pressure on the accelerator the same.
Rough Idling
Finally, whether fuel-starved or fuel-stuffed, your engine will idle roughly if you have a malfunctioning MAF sensor. In severe cases, the engine might stall.
Give Scotty’s Automotive in Montague, NJ, a call if you suspect you have a bad mass airflow sensor. We can test the sensor and replace it if necessary.
