Bad Mass Airflow Sensor Symptoms - University Auto Repair (2024)

FAQs

Bad Mass Airflow Sensor Symptoms - University Auto Repair? ›

A bad MAF sensor can cause your vehicle to experience poor drivability issues such as engine stalling, jerking or hesitation during acceleration. This could happen while speeding up on the highway on-ramp or cruising down a city street.

A bad MAF sensor can cause your vehicle to experience poor drivability issues such as engine stalling, jerking or hesitation during acceleration. This could happen while speeding up on the highway on-ramp or cruising down a city street.

As was mentioned, air/fuel ratio and misfire codes may also point to a problem with the MAF sensor (though, there are many other possibilities, as well). Keep in mind: Sometimes, a bad MAF sensor won't set a code, especially on older vehicles with a type of self-diagnostics called OBD-1.

The engine won't receive the proper airflow if you have a faulty mass airflow sensor. This, in turn, can lead to your car running roughly or the engine misfiring. That happens because the imbalance means that your powertrain control module can't determine how much fuel your engine needs to run.

It is not uncommon for an engine to run a little rough and not idle properly initially after replacement. A road test is often needed for other actuators and sensors on the engine to re-calibrate and adjust. In some cases the base idle or other parameters may need to be reset using the relevant diagnostic equipment.

Check Engine Light: A failed MAF sensor may trigger the check engine light to come on. Stalling: A failing MAF can cause the engine to stall by sending incorrect readings to the engine computer. Black Exhaust Smoke: Black exhaust smoke is a sign that there is too much fuel in the air/fuel mixture.

If the MAF sensor becomes dirty inside and/or begins to fail, you'll notice issues like longer cranking time when starting the engine, hesitation or jerking when you accelerate, rough idling or stalling and sometimes black soot/smoke exiting the tailpipe. You also may notice a decrease in fuel efficiency.

The average cost for mass air sensor replacement is $452 to $524. Enter your vehicle's information to see how much mass air sensor replacement costs in your local area.

No, it's not a good idea to trick a mass air flow sensor.

If you try to bypass your mass air flow sensor, you may get lower gas mileage and have to fill up with fuel more often. It can also lead to other car problems, like trouble starting, trouble accelerating, and black exhaust smoke.

If the MAF is dead or dirty, it won't send the proper readings to the ECM, which can cause starting problems.

Can I just unplug my mass airflow sensor? ›

When the car runs with the MAF unplugged the MAFis bad, trying to drive with it unplugged it will not accelerate properly and might leave you stranded. It will not damage any other parts, just be aware it may go into fail-safe or quit accelerating all together. So you need to replace it ASAP.

A mass air flow typically last between 80,000 miles to 150,000 miles. Proper maintenance of the mass air flow and cleaning it will help prolong its life. However, there are a few vehicle symptoms that will tell you when it is time to replace the air flow sensor. The first symptom is hard starting.

When you remove the MAF sensor, your vehicle's engine control module will need to reset. Removing the battery terminal and discharging the battery for 10 minutes will force a full ECM reset.

After replacing the MAF sensor, it's essential to verify it works properly. Start your vehicle with your code reader connected and observe its performance in the live data, if your tool is equipped with it. If the symptoms have disappeared and the Check Engine light doesn't return, you're in good shape.

The MAF sensor has the biggest impact when the engine is being started and is the engine is running cold. It might make the engine hard to start and idle. Acceleration would be poor.