How To Test The MAF Sensor (1992-1993 3.3L V6 Pontiac Grand Am)

This tutorial will help you test the mass air flow sensor (MAF) in 3 simple test steps.

You don't need any expensive diagnostic equipment to test the MAF sensor. In this tutorial, I'll show you how to test it using a multimeter that can read Hertz frequency.

If you need to just clean the MAF sensor, you can find the tutorial here: How To Clean The MAF Sensor (GM 3.3L 3.8L) (at: troubleshootmyvehicle.com).

NOTE: This is an ON CAR test -no need to remove the MAF sensor from its place to test it.

You can find this tutorial in Spanish here: Cómo Probar El Sensor MAF (1992-1993 3.3L V6 Pontiac Grand Am) (at: autotecnico-online.com).

APPLIES TO: This tutorial applies to the following vehicles:

• 3.3L V6 Pontiac Grand Am: 1992, 1993.

Other GM vehicle MAF sensor test tutorials:

• How To Test The GM MAF Sensor (3.1L, 3.4L, 4.3L, 5.0L And 5.7L)
• How To Test The MAF Sensor (GM 3.8L V6 1996-2005)
• How To Test The MAF Sensor (GM 4.8L, 5.3L, 6.0L, 8.1L)
• How To Test The GM MAF Sensor Express And Savana Van (2003-2008)

Common Symptoms Of A Bad MAF Sensor

The mass air flow sensor on your 3.3L V6 Pontiac Grand Am is a key component of the fuel injection system. So when this bad boy fails, engine performance and driveability will suffer.

You'll see one or more of the following symptoms when the MAF sensor fails:

• Check engine light illuminated on your instrument cluster.
• MAF sensor trouble code stored in your vehicle's fuel injection computer's memory:
  • Code 34: Mass Airflow (MAF) Sensor
• Lack of power when accelerating the engine/vehicle.
• Black smoke coming out of the tailpipe.
• Bad gas mileage.
• Engine idles rough.
• Engine starts but immediately stalls.
• Extended engine cranking (you've got to crank the engine a long time for it start).

You can find out more about the MAF sensor here: What Does The MAF Sensor Do? (3.3L V6 Pontiac Grand Am) .

What Tools Do I Need?

You'll need a few basic/simple tools to be able to diagnose the MAF sensor on your 3.3L Pontiac Grand Am.

You'll need:

• A multimeter that can read Hertz frequency. If you don't have one and would like to buy one, check out my recommendations here: Buying A Digital Multimeter For Automotive Diagnostic Testing.
• A wire piercing probe or a back probe to be able to access the signal within the MAF sensor's output signal wire. To see what this tool looks like, click here: Wire Piercing Probe.
• Although not an absolute must, a code reader or a scan tool to be able to extract any codes registered in the fuel injection computer's memory.

As you can see, there's nothing in the list above that will break the bank!

Circuit Descriptions Of The MAF Sensor Connector

As you're probably already aware, there are three wires sticking out of the MAF sensor's connector.

Here's a basic description of the job each wire does:

Terminal	Wire	Description
A	Yellow (YEL)	MAF Signal
B	Black with white stripe (BLK/WHT) or Black (BLK)	Ground
C	Pink with black stripe (PNK/BLK) or Pink (PNK)	12 Volts DC

To test the MAF signal circuit I recommend that you use a wire-piercing probe or a back probe. You can see what this tool looks like here: Wire Piercing Probe.

IMPORTANT: All of the tests are ON CAR TESTS, do not remove the mass air flow sensor from the vehicle or from its plumbing.

Where To Buy The MAF Sensor And Save

The following links will help you to comparison shop for a known automotive name-brand MAF sensor (no knock-offs) for your 1992-1993 3.3L V6 Pontiac Grand Am:

How Does The MAF Sensor Work?

The sole purpose of the MAF sensor is to measure the amount of air entering the engine. It accomplishes this by means of two hot wires. As air passes over these hot wires, the MAF sensor measures how fast and how much they cool down.

It is then able to calculate the amount of air entering the engine and sends this information to your 3.3L V6 Pontiac Grand Am's fuel injection computer.

It is important to note, that as more air enters the engine, the greater the output of the Hertz frequency signal that the MAF sensor produces.

In plain English this means that the MAF sensor's signal increases as the engine accelerates and that the signal decreases as the engine decelerates.

If the MAF sensor is working correctly, it's Hertz signal will increase/decrease as you accelerate/decelerate the engine.

If the MAF sensor is bad, then it's Hertz signal will stay stuck in one value as you accelerate/decelerate the engine. It's as simple as that!

TEST 1: Making Sure The MAF Sensor Is Getting 12 Volts

To get our MAF sensor diagnostic under way, we're going to make sure that it's getting 10 to 12 Volts DC.

The wire that supplies these 10 to 12 Volts is the wire labeled with the letter C in the photo above.

On your specific vehicle, this wire may be a pink with black stripe (PNK/BLK) wire or a pink (PNK) wire.

Testing the presence of voltage in this wire is a matter of doing a simple multimeter voltage test.

These are the two steps:

1. 1

   Put the multimeter in Volts DC mode.

2. 2

   Disconnect the MAF sensor from its electrical connector.

3. 3

   With the red multimeter test lead and an appropriate tool, probe the wire labeled with the letter C.
   
   CAUTION: If you probe the front of the female terminal, be careful not to damage it with the multimeter test lead.

4. 4

   Connect the black multimeter test lead to the battery negative (-) terminal.

5. 5

   Turn key to the ON position but don't crank or start the engine.

6. 6

   You should see 10 to 12 Volts on the multimeter.

Let's take a look at what your test results mean:

CASE 1: The multimeter registered 10 to 12 Volts. This is the correct and expected test result.

Your next step is to go to: TEST 2: Making Sure The MAF Sensor Is Getting Ground.

CASE 2: The multimeter DID NOT register 10 to 12 Volts. Without this voltage the MAF sensor will not work.

Your next step is to find out why this voltage is missing and resolve the problem.

Once power is restored to this wire, the MAF sensor will function again.