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

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car in shop three times for major fuel leaks

Hi there. Due to the age of the vehicle, the lines will commonly rot out causing this. Due to the fact that there is fuel in these lines, this accelerates their deterioration. The only way to prolong the life of...

Q: What can cause your car to stall out and what can cause the rpms to go up?

It sounds like you are getting a bad reading from the crankshaft or camshaft sensor. Have the computer scanned and the data stream monitored for problems with the two sensors to see which one is causing the stall and erratic...

Q: RPM issue. Car can't produce enough power. Idles low and caps at low RPM.

Hey there, thanks for writing in about your 2001 Nissan Sentra. It sounds like you may have a throttle position sensor issue or idle air control valve issue. If the catalytic convertor was not replaced, it could also still be...

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...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...