Skip the auto shop - Our mechanics make house calls

Q: How Often Does the Mass Air Flow Sensor Need to Be Replaced?

asked by on

How often does the mass airflow sensor need to be replaced?

A: Mass airflow sensors (MAF) have no expirati...

Mass airflow sensors (MAF) have no expiration date. They are not included on the manufacturer’s scheduled maintenance list of things to replace based on mileage, like spark plugs or filters. They can remain in service indefinitely as long as they continue to function correctly.

However, MAF sensors are critical to engine performance, good gas mileage, and low emissions. They are also fairly fragile and sensitive to contamination. A bit of basic preventative maintenance awareness can help an MAF stay alive and healthy as long as possible. Since the function of an MAF is to measure all the air flowing into the engine, they have a LOT of air flowing through them. Try to imagine 9,000-10,000 gallons of air flowing through your engine for every 1 gallon of gas burned! That much air carries a lot of fine dust and particulates of all types. It is the job of the air filter to keep that all that junk off of the MAF, as well as out of your engine. So replace the air filter when recommended, keep the inside of the air filter box very clean, and be sure the ducts between the air filter box and the throttle body are all securely clamped and airtight.

Another simple maintenance item that is commonly neglected can impact the cleanliness of the MAF, the PCV valve. It should be replaced according to the manufacturer’s recommendations based on mileage. If the PCV valve becomes restricted, it can cause crankcase vapors to back up through the engine’s breather system and leave oily deposits on the MAF. If the MAF gets dirty, it becomes less accurate and a loss of performance will usually be noticed. A trouble code will get logged in the computer, and the Check Engine Light will illuminate.

Many times, MAFs are removed, cleaned with a spray cleaner, and reinstalled. This is not a permanent fix. For a more long-lasting repair, have the MAF replaced.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Intermittent failure to respond to throttle

Hello - wow, an older classic! Your 300TE utilizes Bosch Continuous Injection System (CIS) which varies fuel pressure more dynamically than more contemporary injection systems. I would suspect fuel pressure is the problem, both for the inability of the engine...

Q: two front wheel speed sensor died

As long as the light is out and does not come back on, then the system is working as it should. The problem with the sensors may be an intermittent problem in the sensors or the wires going to the...

Q: Service engine warning, MAF code and O2 sensor code, along with check suspension light are turned on

Hello, it sounds like you have quite a few things going on. I am going to do my best to break them down for you. First if the engine is very loud when idling and the belt has...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.