What To Do After Replacing Mass Air Flow Sensor? 2 Secrets Must Know

What to do after replacing mass air flow sensor? Making the replacement only is never the best idea for sure.

Mass airflow (also MAF) sensor is one of the key engine components of vehicle technology.

This part stands between the intake manifold and an engine’s air filter. And it joins in the electrical engineering fuel injection system.

This vehicle part calculates the amount of air that enters the engine. Not only that, but this calculation also relates to the amount of injected fuel needed for rotating machines.

However, a failed/contaminated mass flow sensor could lead to miscalculation. And it probably causes many additional damages over time.

As a solution, replacement is always a must to fix these problems. Thus, mechanics often choose to replace the new ones.

Before learning about how to change a mass air flow sensor, what to do after replacing mass air flow sensor?

What To Do After Replacing Mass Air Flow Sensor
Mass Air Flow Sensor

What To Do After Replacing Mass Air Flow Sensor?

Disconnect The Battery

When you get the mass air flow sensor installation done, the process has not finished yet. Instead, it needs several additional steps for a complete replacement.

After changing a mass air flow sensor, you should disconnect it from the car battery for around 15 minutes. It is not the same as how to disconnect mass air flow sensor. You can follow the steps as below.

  1. Turn the engine off. Noone can disconnect the battery without doing this step. Also, we suggest using some safety equipment such as goggles and gloves.
  2. Find the negative terminal of the battery. If you find it difficult, let’s ask a mechanic for a favor. He will help to determine the exact location.
  3. Use a wrench to loosen the negative terminal nut.
  4. Remove the negative connecting point.
  5. Repeat the process with the positive terminal of the battery.
  6. Disconnect the battery. Although the battery gets completely disconnected at this point, you should remove it from the tray. The additional step helps to see whether the battery needs a replacement.

So, what happens if you disconnect mass air flow sensor?

The disconnection helps to reset the factory setting and remove old parameters. At the same time, it starts recording the new data with the new replacement.

Do A Proper Frequent Maintenance

Indeed, the automobile part for MAF does not always appear on the list of maintenance schedules. However, you should not ignore this part since it occasionally degrades.

Proper periodic maintenance can help to reduce the need for replacement.

If you are still so confused, the following steps are what to do. The process often takes about minutes only. So, let’s follow them one by one.

Replace MAF sensor
MAF sensor maintenance

Step 1: Finding The Air Intake System

Every car does not hit the same when it comes to structuring. Hence, we suggest checking the repair manual to know exactly where the air intake system is.

For example, the intake of a Ford E250 lies under the hood. And it is often so dirty.

Step 2: Taking Part Air Intake System To Find MAF Sensor

The air intake system consists of tubes made of plastic or metal. By removing this part, you will see a MAF sensor located between the engine and the filter.

For instance, the Ford cars often have this part sitting behind the filter. This location is quite easy for you to reach and remove.

After removing mass air flow sensor, you can check whether a replacement is in need or not.

Step 3: Cleaning The MAF Sensor

  • Start the vehicle engine. Many drivers surely do not want to do this job without the air filter. But it is still ok for a short time (some minutes).
  • Spray the cleaner you can buy from hardlines (retail) providers. And it is normal if the engine starts stalling.
  • After each time of spraying, use the squirt to keep the engine from breathing and operating. The more parts of the MAF sensor you can spray, the better this job will get done.

While doing step 3, you could see the code like OBD2 or P2197. It indicates that there is too much air entering the engine. And this amount is not suitable for the current amount of fuel provided.

But those codes come during the cleaning process. Hence, it may not be the true problem. So, it is safe for you to ignore them for a while.

Step 4: Reassembling The Air Intake System

Now you finish the cleaning. It is time to care about how to install mass air flow sensor in its original place.

If the old air filter is too dirty, we suggest replacing the new one. Then reinstall all parts one by one, like when you take apart them.

Step 5: Using A Scanner To Clear The Codes

In Step 3, we have already mentioned some codes. Now, you can clear all of them with a scanner. 

When Does MAF Sensor Go Bad & Need A Replacement?

The automobile part for MAF monitored by on-board diagnostics tends to work with a reduction in performance over time. It is a normal issue due to the air moving activity through vehicle parts.

In other words, this process encourages debris and dust to stick to the mass air flow sensor tool and electrical components.

A dirty construction can cause the MAF to stop working. Models like Toyota often show a higher rate of failure. So, it would be best if you had your vehicle checked by a mechanic.

In case of some following symptoms, it is time for the mass air flow sensor replacement.

MAF Sensor Go Bad
Mass air flow sensor replacement

Engine Light

We view it as one of the most potent signs of a failed automobile part for MAF. Sometimes, it also points out several other problems.

So, a mechanical check will help to have an exact conclusion when you see the light.

Jerking/ Hesitation When Accelerating

You could notice an unusual sudden jolt of power or hesitation when speeding up the car. These signs happen as a result of MAF sensor-related issues.

Some drivers may ignore and think that they do not matter. However, driving a car with these problems is relatively dangerous.

It would be better to call any experts in systems engineering. A deep understanding of systems engineering can help them detect exactly what problems are.

Misfiring Running

Another drawback coming with a fault automobile part for MAF is the misfiring running.

Let us explain.

The MAF, without a proper operation, can affect the PCM (standing for the powertrain control module). This part manages the vehicles’ transmission, engine, and other systems.

A wrong part probably leads to PCM’s misunderstanding about the fuel amount needed. Simply put, the engine could run with too little or too much fuel.

In other words, the throttle is out of control. The result of this incomplete process is a rough misfiring then.

Lean Idling

The vehicle seems to struggle with power and stall a lot recently. It is a problem where too much air but too little fuel enters the engine. For days, the dirt has built upon the MAF’s wire.

Due to this failure, the combustion inside engine components starts degrading. And you need to ask an automotive professional for help.

Black Exhaust Smoke

Something may go wrong with a sign that your car produces a lot of black exhaust smoke. It can be the result of several different problems.

That said, the possibility of a damaged automobile part for MAF is still quite high.

Because of a damaged area, the engine control model is prone to improper calculation. It cannot give accurate data of the fuel injection. Consequently, the black smoke comes.

Difficulty In Starting the Engine

A bad automobile part for MAF can also spoil the air/fuel mixture.

When experiencing a failure, the mixture tends to be off-balance. This problem troubles the engine.

As a result, the vehicle cannot operate as normal. And sometimes, it can be a possible reason why the car won’t start right after turning off.

Poor Fuel Efficiency

This case and the misfiring running above hit nearly the same. A part at fault results in an inaccuracy of PCM.

Hence, your vehicle could consume more fuel than it usually does. Generally speaking, the engine burns the fuel more quickly than usual.


To sum up, resetting the car battery is what to do after replacing mass air flow sensor first. Moreover, proper maintenance after that also holds a key.

A better understanding of the electrical connector or any manufactured goods will help to reduce replacement.

For further support, feel free to drop us a line. And we will be back soon with many more helpful write-ups.

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