What To Do After Replacing Mass Air Flow Sensor – Easy Tips

What to do after replacing mass air flow sensor involves straightforward things, and there’s no need to panic. For instance, you should ensure you’ve installed the sensor correctly, reset the ECM, and then go for a test drive.

Replacing Mass Air Flow Sensor

See more of these tips and the details below, including how much it costs to replace a MAF sensor professionally. You’ll also find answers to questions many car owners like you frequently ask, so read on.

What Should You Do After Replacing a Mass Air Flow Sensor?

What you should do after replacing a mass air flow sensor is double-check your installation to ensure you implemented every step correctly. Check the installed sensor and verify it’s the correct part for your vehicle. An ECM reset and test drive may also be necessary.

The mass airflow (MAF or mass airflow) sensor plays a critical role in the smooth running of your vehicle’s engine. It’s between the air intake manifold and the engine’s air filter housing. The MAF sensor calculates the air amount entering the engine block. It then sends this information to the engine control module (ECM), which needs it to control the fuel injection process.

A malfunctioning MAF sensor can send misleading signals, affecting your engine’s performance. It may also cause many additional issues over time. The solution is to have it replaced. After spending time replacing the sensor, you expect the vehicle’s driveability issues will be fixed automatically.

However, sometimes that doesn’t happen, and the car runs worse with new MAF. As mentioned, you don’t need to freak. Just implement one or more of the troubleshooting tips discussed in detail below:

Double-Check Your Installation

A faulty installation is a common reason a vehicle may not work correctly after mass airflow replacement. The MAF sensor replacement is easy. However, anyone can make a mistake, such as missing a step. As mentioned, any errors during the replacement will result in your new sensor not functioning as it should.

So, ensure you follow the installation instructions correctly in the car factory service manual. Double-check all your steps to ascertain that you didn’t hook anything up incorrectly. Should you disconnect battery when replacing mass air flow sensor? Yes, doing so will avoid the risk of a short circuit, which can lead to further engine problems.

MAF Sensor Replacement

Many ask how to trick a mass air flow sensor, which is done by connecting a resistor to the sensor’s signal wire. But bypassing the MAF is a bad idea as it can trigger issues with your vehicle, including reduced fuel efficiency.

Ensure Your New MAF Sensor Is Correct

You might have installed the wrong sensor, so the issues in your vehicle still need to be fixed, as the ECM is still receiving misleading signals from the old sensor. So, ensure you have the correct part. Carefully read the number on the old sensor and compare it with the one in the new part’s description. The two numbers should match.

If that’s not the case, you’ll have to order a suitable component. Keeping your vehicle’s repair manual handy is essential to check the correct specs to avoid costly mistakes.

Reset the PCM

When the MAF sensor goes bad, your car’s ECM may alert you by sending a diagnostic trouble code. That should typically turn on the check engine light. But if you find the engine light still on after replacing mass air flow sensor, it indicates that the vehicle’s computer still has the records of the old sensor stored in its memory.

Resetting the ECM (or what some call resetting the trouble codes) allows it to clear that previous data. After that, it can begin receiving new signals from the newly installed sensor and adjust the air-fuel mixture accurately. Without the ECM resetting, your engine may run rich or lean due to an imbalanced fuel-air ratio. The vehicle can often reset itself and continue using the recently installed sensor, but it can take time.

Checking Engine Light

So, how long does it take for a new MAF sensor to work? The time depends on your car model; some cars could require multiple driving sessions. The best thing to do is to reset the car manually. One way to do so is by using an OBD2 scan tool.

Alternatively, you can reset the ECM by disconnecting the car battery for a few minutes. However, one disadvantage of this method is that all your radio presets, clock settings and seat memory will also be erased. If you still want to continue with it, turn the engine off, open the hood, and identify the battery’s negative terminal. Remove the terminal with a wrench and leave it disconnected for about 15 minutes.

Another option to reset your car’s computer is by idling it. Start the engine and let it idle for at least 30 minutes. Once that time has elapsed, turn the car off and wait a few minutes before restarting it.

Drive the Car

Taking your vehicle for a test is necessary once you’ve replaced the bad MAF sensor. As mentioned, the ECM can reset automatically, but you may need to help by driving the car for at least 20 minutes. Also, a driving session is likely required after resetting the sensor manually. It doesn’t matter the method you’ve used to reset the engine control module.

Whether disconnecting the battery with an OBD2 scanner or letting the engine idle, a drive will enable the ECM to discover and communicate with the new sensor. During the drive, pay attention to how the engine behaves. For example, does it run rough or produce black smoke?

Does the check engine light come on? Also, avoid turning on the radio to help you hear how the engine runs. If the engine warning light illuminates the dashboard or you notice any performance issues, you’ll need a closer look at the sensor again. Hopefully, there will be no issues, and your new sensor will work perfectly.

If the car won’t start after replacing mass air flow sensor, that may be a sign of a more complex problem. Contact a professional to help you diagnose it. Most reliable local auto repair shops have advanced diagnostic tools to quickly find and fix engine problems. Once the vehicle is repaired, keep the engine and air filter clean to prevent premature failure of the sensor and other components.

Note that many things can cause a mass flow sensor to fail. One is the precision at which the sensor is expected to deliver, which makes it a delicate device. Dirt, debris, grease, and carbon buildup can easily contaminate it. The contamination can sometimes happen before it’s 25,000 miles old, depending on your car model.

Check Out for Any Technical Service Bulletin

You should check out if there are any issues associated with your car type known to its manufacturer. All automakers release technical service bulletins to reveal common problems with the model. The bulletins are meant for auto dealer service departments but are also available for free in the public domain.

Open the NHTSA website and enter your vehicle identification number (VIN) in the search bar. Any available information about your car model, including the recalls and current service bulletins, will appear. After that, you can make an informed decision on how to get your car fixed.

What Is the Cost of Replacing the Mass Air Flow Sensor?

The cost of replacing the mass air flow sensor professionally is $220 on average. You can expect to pay a minimum of $80 and a maximum of $380 for parts and labor. The exact amount will vary, depending on your car model, the quality of the part, and location.

An aftermarket mass airflow sensor costs roughly $30 for a typical car and up to $300 for high-end vehicles. That means you’ll likely pay an average of $165 for the part alone. However, the price could go higher for a better quality OEM sensor. As stated, the installation process is straightforward because the sensor is in an easy-to-access spot on the engine.

Cost of Replacing Sensor

Even with the most standard mechanical experience, the job should take only a few minutes. Thus, if you decide to install the part yourself, the replacement cost will be more or less $165. But if you need help, hire a mechanic to ensure the part is installed correctly to avoid issues. Depending on your location, a professional will charge you one hour’s labor, anywhere from $50 to $80.

So, assuming you spend an average of $65 on labor, the total cost of replacing the bad mass air flow sensor comes to $220, as stated above. As you can see, 75 percent of the expense will be the cost of the part. Therefore, allowing an expert to help do the replacement will be acceptable. In any case, the expert will diagnose and fix the engine if any issues, such as a rough idle after replacing mass air flow sensor, arise.

Frequently Asked Questions

How Long Do the Air Flow Sensors Last?

The air flow sensors last at least 300,000 miles or as long as the car does. However, that usually doesn’t happen due to several reasons. For example, excess carbon can build up on the MAF sensors over the years, making it difficult for them to continue functioning as intended.

What Is the Easiest Way To Know if a MAF Sensor Is Faulty?

The easiest way to know if a MAF sensor is faulty is to observe the various tell-tale signs.

Faulty MAF Sensor

A failing mass airflow sensor will often cause stalling issues, rough idling, sudden jerking motions, and poor acceleration. You’re also likely to experience poor fuel economy when your sensor fails.

How Many Mass Airflow Sensors Does a Car Have?

A car has two mass airflow sensors: the hot wire and the vane meter. Both don’t use a technology that measures mass airflow directly. However, they still enable the ECM to accurately determine the intake air flow rate with the help of other sensors and inputs.

Do You Need to Program Your New MAF Sensor?

No, you don’t need to program your new MAF sensor because it’s impossible. What you can reset is the engine control unit (ECU). Resetting the ECU enables it to clear the data of the previously installed sensor and start reading the new one for improved engine performance.

What Are the Common Drawbacks of a MAF Sensor?

The common drawbacks of a MAF sensor include premature failure due to contamination by dirt, debris, and other elements.

Installing Air Flow on Car

That untimely death is one of the most common sources of engine problems. Also, any amount of trace material can impact the sensitivity of its wires, leading to engine performance issues.

Is Replacing the Mass Air Flow Sensor an Easy Task?

Replacing the Mass Air Flow Sensor is a fairly straightforward job that can be done by most car owners. However, it is essential to identify the exact issue before jumping to conclusions. If your vehicle experiences symptoms like rough idling or a decrease in fuel efficiency, it may indicate a faulty sensor. Consulting a professional technician is advisable as these signs could also be related to other components such as the oil pressure switch or sensor.


Our article on what to do after replacing mass air flow sensor has offered enough information to help you get your car back in shape.

The following is a recap:

  • Replacing the MAF sensor should automatically fix any engine performance issues you had with the old sensor.
  • However, that doesn’t usually happen, and there are one or more things you might need to do after the procedure.
  • These include double-checking the installation to ensure you did everything accurately and used the correct sensor for your car make and model.
  • You may also need to reset the ECM by using an OBD2 scan tool, disconnecting the battery’s negative terminal for about 15 minutes, or idling the engine for at least 30 minutes.
  • Driving the car after the replacement may also be necessary to enable the ECM to start receiving accurate signals from the newly installed sensor and adjusting the fuel-air mixture accordingly.

Implement one or more of the above tips and get your engine performing as intended. Don’t hesitate to get in touch with an expert if you need further assistance troubleshooting any problems after replacing MAF sensor.


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