The mass airflow (MAF) sensor is an important component of the engine management system on the 3.4L V6 equipped Chevrolet and Pontiac vehicle.
In this article, I'm going to answer some of the most commonly asked questions about the MAF sensor.
I've also included a link to the diagnostic test tutorial you'll need to test the MAF sensor with a multimeter.
Contents of this tutorial:
APPLIES TO: This tutorial applies to the following vehicles:
- 3.4L V6 Chevrolet Impala: 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Chevrolet Lumina Minivan: 1996.
- 3.4L V6 Chevrolet Monte Carlo: 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Chevrolet Venture: 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Pontiac Aztek: 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Pontiac Grand Am: 1999, 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Pontiac Montana: 1999, 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Pontiac Trans Sport: 1996, 1997, 1998.
What Does A MAF Sensor Do?
To be able to calculate the correct amount of fuel to inject into the cylinders (as the engine runs), the fuel injection computer needs to know how much air is entering the engine.
The component that is tasked with measuring the amount of air the engine is breathing and then sending this information to the computer is the MAF sensor.
Here are some more specifics:
- The MAF sensor is designed to produce an increasing output signal as the engine accelerates (and takes in more air).
- Once the throttle plate starts to close and the engine decelerates, the MAF sensor's output signal decreases.
What Happens When A MAF Sensor Goes Bad?
When the mass air flow sensor fails, it simply stops reporting the amount of air entering the engine as it runs.
Without any engine air intake information being sent to the fuel injection computer, engine performance and driveability will suffer.
In the next section, I'll go into some of the specific symptoms you'll see when the MAF sensor fails.
What Problems Can A MAF Sensor Cause?
A bad mass air flow sensor will cause one or more of the following symptoms:
- Bad gas mileage.
- Lack of power.
- Black smoke coming out of a tailpipe.
- Check engine light is illuminated by one or more MAF sensor trouble codes.
- Rough idle.
- The engine may start and immediately stall.
- Extended engine cranking (the engine has to be cranked a long time for it to start).
- The engine may not start.
- One of the following MAF diagnostic trouble codes illuminating the check engine light:
- P0101: MAF Sensor Performance Problem.
- P0102: MAF Sensor Circuit Low Frequency Signal.
- P0103: MAF Sensor Circuit High Frequency Signal.
How Can I Find Out If The MAF Sensor Is Bad?
The only way to be 100% sure that the mass airflow sensor is bad, without replacing it to find out, is by testing it.
There are many ways to test the MAF sensor, one of them is with a multimeter. This is the basic MAF sensor multimeter test procedure:
- Check for MAF sensor trouble codes with a code reader or scan tool.
- Make sure that the MAF sensor is receiving 12 Volts.
- Make sure that the MAF sensor is receiving Ground.
- Make sure that the sensor's MAF Hertz frequency signal increases/decreases as the engine is accelerated/decelerated.
- To test the MAF sensor's Hertz frequency signal, you'll need to use a multimeter with Hertz frequency measurement capability.
If the MAF Hertz frequency signal does not increase/decrease as you accelerate/decelerate the engine, then you can conclude that the MAF sensor is bad and needs to be replaced.
Testing the mass airflow sensor is something that you can do without having to take it to an automotive repair shop.
I've written a tutorial on how to test it with a multimeter, you can find that tutorial here: How To Test The MAF Sensor (3.4L V6 Chevrolet, Pontiac).
Can I Drive My Car With A Bad MAF Sensor?
Depending on the severity of the symptoms that the bad MAF sensor is provoking in your Chevrolet (Pontiac) vehicle, you probably won't be able to drive it.
Now, even if the car were drivable, you should avoid doing so.
Where Can I Buy The MAF Sensor?
The following links will help you to comparison shop for a known automotive name-brand MAF sensor (no knock-offs) for your 3.4L V6 Chevrolet or Pontiac vehicle:
More 3.4L V6 Chevrolet, Pontiac Tutorials
You can find a complete list of 3.4L V6 Chevrolet (Pontiac) tutorials in this index:
Here's a small sample of the tutorials you'll find in the index:
- How To Test Engine Compression Test (3.4L V6 Chevrolet, Pontiac).
- How To Test A Blown Head Gasket (3.4L V6 Chevrolet, Pontiac).
- What Does The CKP Sensor Do? (3.4L V6 Chevrolet, Pontiac).
- What Does The Throttle Position Sensor Do? (3.4L V6 Chevrolet, Pontiac).
If this info really saved the day, buy me a beer!