Having trouble with acceleration, or noticing your miles per gallon decreasing?
Did the check engine light pop on, and you suspect a bad mass air flow sensor?
Before you get a replacement, there’s a chance it’s just really dirty. A good cleaning could very well solve any MAF sensor-related engine performance problems. Cleaning a dirty MAF sensor could also save you a fair sum rather than installing a new one.
If you’re unsure what to do, we’ll show you how to clean a mass air flow sensor.
Keep reading.
This Article Contains
- How to Clean a Mass Air Flow Sensor
- When Should You Clean the Mass Air Flow Sensor?
- 4 FAQs about Cleaning the Mass Air Flow Sensor
How to Clean a Mass Air Flow Sensor
Cleaning the mass air flow sensor is quite an easy thing to do. However, you should use a dedicated MAF cleaner, as this sensor is very sensitive. The sensor measures air flowing into the intake manifold, impacting your airfuel ratio. Any reading errors will affect your vehicle’s fuel efficiency.
TIP: If you’re unsure how to go about this, always get a mechanic to help you.
Before you start:
- Make sure the engine is off and cool.
- Wear gloves and safety glasses for further protection as you clean the sensor.
1. Unplug the MAF Sensor
The first step is to locate the mass air flow sensor. It’ll be close to the air intake box and before the throttle body. You could also trace the wiring harness to the electrical connector that attaches to the MAF sensor.
To help you identify it, the MAF sensor box typically has an arrow pointing in the direction of the airflow toward the intake manifold. If you still have trouble locating it, check the vehicle manual.
Once located, unplug the electrical connector from the vehicle’s electrical system to the mass airflow sensor.
2. Detach the MAF Sensor From the Engine
Loosen any brackets, fasteners, or clamps and remove the mass airflow sensor.
Depending on the sensor configuration (vane, hot wire, etc.), you might remove it directly from its housing, remove the sensor from the air duct and air filter box, or simply detach the entire sensor assembly and air box cover together.
3. Clean the MAF Sensor
Make sure no part of your hand, the MAF cleaner can, or cleaner straw touches the delicate sensor element. This is the part you’ll want to clean.
Keep the straw about 100-120 mm away (or as instructed on the can) and start spaying liberally over a container or towel that can catch runoffs. About 10-15 sprays should be sufficient. The cleaner formula is strong enough that you won’t need to scrub (which would damage the sensor anyway).
Let the mass air flow sensor dry completely — this should be fast.
Additional Step: Clean the air intake housing to remove dust, debris, and any oily film, which will get back on the MAF sensor once you reattach it. You can use soapy water, carb cleaner, or wet a rag with MAF sensor cleaner to clean the plastic air intake housing. Dry with a lint-free rag. The entire upstream of the MAF sensor should be clean.
4. Reattach the MAF Sensor
Reattaching the sensor is the reversal of your removal process. Make sure the MAF sensor is completely dry before doing this.
Reinsert the sensor into its housing or attach it to the intake air duct and air box. Tighten any fasteners, clamps, or brackets. Then, reconnect the wiring harness to provide an electrical connection to the sensor. Also, inspect the wires to make sure they’re in good condition — damaged or loose wires can affect the sensor signal.
If your check engine light had previously lit up, turn on the engine to see if cleaning the MAF sensor has resolved the problem.
Precautions
Here are some vital reminders when cleaning the mass airflow sensor:
- Only use an MAF sensor cleaner (such as CRC MAF Cleaner). The proper cleaner will have special features like fast-drying and leaving no residue on the sensor.
- Do not reinstall the sensor until it’s completely dry.
- Do not use cleaners like WD40, carb cleaner, or brake cleaner, as these can damage the sensor element and even warp the plastic housing.
- Do not poke the sensor with a Q-Tip to scrape off deposits.
Next, let’s find out if MAF sensor cleaning should be a regular activity.
When Should You Clean the Mass Air Flow Sensor?
The MAF sensor is often not a thing people think of. However, you should get the mass airflow sensor cleaned every time you change the air filter or every 6 months. The sensor is located near the air filter box, so accessing it at the same time is convenient.
You should also consider cleaning it if you notice signs related to a dirty MAF sensor, such as poor fuel efficiency, erratic idling, or your check engine light turning on.
If issues persist after you clean the MAF sensor, the sensor may require replacement.
Still have questions on the MAF sensor cleaning?
We have answers.
4 FAQs about Cleaning the Mass Air Flow Sensor
Let’s go through some queries related to cleaning the MAF sensor and their answers:
1. What Are the Signs of a Dirty Mass Air Flow Sensor?
MAF sensors are used almost exclusively on vehicles with fuel injection. So, if your car has a fuel injection system, you’re bound to have an MAF sensor.
A dirty MAF sensor can impact engine efficiency in several ways.
Here are some symptoms:
- Check engine light turns on with these p-codes: P0100, P0101, P0102, P0103, P0104, P0105
- Engine hesitates during acceleration
- Engine displays erratic idle
- Engine stalls or has trouble starting
- Engine experiences horsepower loss
- Poor fuel economy
NOTE: Vacuum leaks can exhibit similar engine performance symptoms to a bad MAF sensor, so be aware of that.
2. Why Does the MAF Sensor Get Dirty?
The mass air flow sensor will get dirty if the air filter hasn’t been cleaned or changed in a while, accumulating debris, dust, and pollen.
Using an oiled air filter can also cause those oils to coat the MAF sensor over time.
3. Can You Use Rubbing Alcohol to Clean an MAF Sensor?
No. You should only use an MAF sensor cleaner on an MAF Sensor. Other cleaners or detergents can be too harsh and may damage the sensor element. Touching the sensor to scrub or scrape it can also damage it.
4. How Do You Clean an MAF Sensor Without Scrubbing It?
You will need an MAF sensor cleaner to spray onto the sensor. This method doesn’t require scrubbing or scraping, minimizing potential damage to the sensor element.
Keep Your MAF Sensor Clean for Optimum Performance
The mass air flow sensor is crucial in measuring your vehicle’s air intake. Its readings help the engine computer decide the airfuel ratio, ensuring the correct amount of fuel is delivered so the engine generates the horsepower you need. Keeping the MAF sensor clean ensures accurate readings, maintaining engine efficiency and a steady gallon consumption.
If you need help with your mass air flow sensor (or any other car issues), you can always rely on AutoNation Mobile Service.
We’re a mobile auto repair and maintenance solution. We’re available seven days a week and have an easy online booking process. All repairs and maintenance are covered by a 12,000-mile, 12-month warranty.
Contact us for your MAF sensor issues, and our best mechanics will resolve them right from your driveway.