The mass air flow sensor (commonly abbreviation to MAF) is one of the most necessary engine monitoring sensors. A bad mass airflow sensor can leave your GMC Envoy’s engine to run rough, or even inoperable.

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A MAF sensor actions the thickness of the air entering the input manifold. It passes this details onto her Envoy’s ECU. The ECU offers this information together with other sensor data to regulate the lot of fuel the enters the burning chamber.


If girlfriend do recognize that you need a new mass airflow sensor, lock aren’t as well expensive. And, most of the time they are ideal by the waiting box and also easy come replace.

Faulty Mass airflow Sensor Symptoms: GMC Envoy

When the mass air flow sensor has gone bad, you’ll definitely feel it. Below are the most typical symptoms the a negative or failing MAF sensor:

Idle Issues– her Envoy may run well-off or lean as soon as idling, or the may additionally idle erratically. A rich problem is when there is not sufficient air family member to the fuel in the air/fuel mixture. The exhaust color is normally darker when running rich. A lean problem is as soon as there is too lot air family member to fuel in the waiting fuel mixture. The exhaust color usually doesn’t change. Hard to Start– Without understanding the suitable amount of wait entering into the intake, it deserve to be really difficult for the engine to start. And also when the does, the doesn’t generally run really well. Decreased Fuel Mileage– Fuel mileage have the right to suffer without the ideal air/fuel mixture.
Here a pair of common MAF sensor styles

Envoy negative MAF Sensor Diagnosis

If the MAF sensor has actually gone bad, it’ll cause the examine engine irradiate and administer an OBDII problem code. This is an excellent because it help you narrow down the problem. The two most usual trouble password in relation to the MAF sensor are:

There are other codes related to the mass air flow sensor together well, but these room the most typical ones. Here’s a wonderful video on exactly how to diagnose a negative MAF sensor utilizing a multimeter from Ratchets and Wrenches ~ above YouTube.

Cleaning the Mass air flow Sensor

Often, the mass airflow sensor yes, really only requirements cleaning once they go bad. Some folks recommend utilizing alcohol due to the fact that it’s typically on hand, and also can clean the sensor. This is a negative idea, the can damage the sensor. Offers mass airflow sensor cleaner. It’s yes, really cheap and easily accessible at any kind of parts store. It certain beats the hell out of having to purchase a new sensor.

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Locate the MAF Sensor– It’ll be in between the waiting filter and also the accelerator body. Eliminate the Sensor- Take treatment not to damages the wiring harness or the connector pins that receive the exploit in the MAF. Straightforward hand devices will it is in all the you need to complete the job. Clean the Sensor– now that you’ve gotten rid of your Envoy’s MAF sensor, it’s time come clean it. You’ll need the MAF cleaner. You are not scrubbing anything. Let the chemicals do their job. About a dozen tiny bursts will certainly be all the you need. Replace the Sensor


Replacing a bad MAF sensor deserve to make your Envoy feel favor a brand-new vehicle. An excellent luck through the diagnosis. If over there is anything that you would like to add, you re welcome feel free to leaving a comment below.