How to Deal with MAF Sensor Failure in Volkswagen

Posted on June 2, 2019 by Carson Wileman

Volkswagens are hard working cars that represent decades of the highest quality of German engineering. However, without the correct care and maintenance, these brilliant vehicles can become worn out and start to fail.

In this article, we will be taking a closer look at the MAF sensor of your vehicle and what to do should it fail.

What is a MAF sensor?

MAF sensor is an acronym for Mass Air Flow sensor. This sensor is found under the hood of your Volkswagen. In appearance, it looks like a black cylinder which has many ports and valves that connect to various parts of your car. This sensor mainly interacts with your Volkswagen’s OBD (onboard diagnostic system).

The job of the MAF sensor is to monitor and measure the weight and temperature of air flow entering the engine. It then uses this data to inform the OBD how much fuel to provide the engine to perfectly match the air in the engine.

Put simply, a car needs a mixture of air and fuel to run. The MAF sensor helps provide the air and the OBD helps provide the fuel.

MAF Sensor Types

There are 2 types of MAF sensors: cold-wire and hot-wire. The majority of modern cars utilize hot-wire sensors to monitor air flow. The MAF sensor does this by utilizing a hot wire to keep it at a steady 90 degrees. The sensor measures how much energy is required to do this, which in turn informs it of the amount of air entering the engine.

Why is the MAF sensor important?

Any part which maintains the smooth running of an engine is important. The MAF sensor helps ensure the correct air-to-fuel ratio for optimum performance. If it fails, you truly are in for a whole host of problems and costly repairs.

Symptoms of MAF Failure

There are many potential symptoms of MAF sensor failure in your Volkswagen, below are listed some of the most common.

Rough Idling:  When your Volkswagen is idling, for example at an intersection or red light, if your MAF sensor is failing, you’ll probably notice your engine isn’t idling as smooth as normal. You might experience a juddery vehicle, with loud rumbling coming from your engine. This is due to the incorrect air-to-fuel ratio, as the OBD is trying to guess the amount of fuel needed instead of being provided the right ratio by the MAF sensor.

Tough Ride: Another MAF failure you’ll be hard-pressed not to notice will be how much of a chore your vehicle becomes to drive. It may misfire regularly due to failed fuel ignition and may stop or stall for the same reason.

Fatal Fuel Economy:  A failed MAF sensor will also play havoc with your Volkswagen’s fuel economy, meaning you need to visit the pumps more frequently. The cause, again, is the OBD trying to guess the amount of fuel the engine needs to correctly match the air entering it. Typically, the OBD will over compensate for this lack of information by injecting more fuel than necessary. Therefore, this leads to your car burning through gas far quicker than it used to, impacting your vehicle performance and your bank account.

Engine Repair

In the most severe cases, the misaligned air-to-fuel ratio can damage your engine or its integral parts by putting them under undue stress or strain. This can lead to lengthy and costly repairs and is best avoided with required maintenance.

How to Deal with MAF Sensor Failure

If you feel MAF sensor failure may have occurred, then there are several things you can do. The best option is to avoid failure entirely in the first place, by scheduling routine maintenance. However, once failure has happened, it is possible to replace and repair the MAF sensor at home, if you are mechanically-minded, and there are plenty of guides online to help you do so.

However, for complete peace of mind, your best course of action is to seek professional repair and service from a trusted mechanic. Luckily, if you’re a Volkswagen driver living in the Anacortes, Blaine, Ferndale, Lynden, and Bellingham areas of Washington, then Keith Cox Autobahn will give your car the care and attention it deserves.