The Chevy Lumina MAF Sensor is a vital part of your EFI system. This pass through mass air flow sensor reads information about the air as it passes over hot wire elements inside the MAF. Your Chevy Powertrain Control Module or PCM receives this signal and uses it to determine how much fuel your engine needs.
When this mass air flow sensor becomes dirty, clogged or begins to fail your Lumina will run poorly. Today I’ll be showing you how to test your Chevy Lumina MAF Sensor in a 1997 3.1 liter engine. This mass air flow sensor is a pass through style, meaning it’s mounted inline rather than in it’s own mass air housing.
This particular mass air flow sensor is connected to your air box and intake tract. It’s plugged in using a three pin engine harness and today I’ll be showing you how to test it using a wiring diagram.
Symptoms of a failed Lumina MAF Sensor
There can be several common symptoms of a bad mass air flow meter in your 3.1 liter V6 engine. Some of these symptoms can be annoying and some others can be dangerous or highly troublesome. Here’s just a few of the problems you’ll encounter when the MAF sensor in your Chevy starts going bad.
- Lack of power
- Poor performance
- Bad gas mileage
- Black smoke from exhaust
- Check Engine Light ON – For any number of OBDII check engine codes. Here’s a look at just a few
- P0101 Mass Air Flow System Performance
- P0102 Mass Air Flow Low Frequency
- P0103 Mass Air Flow High Frequency
Your Lumina may also stall or have a rough idle. This is because your engine computer has no idea how much air is entering your engine and thus cannot control the fuel events properly.
Testing your Lumina MAF Sensor for Power
The first leg of this DIY tutorial to testing your mass air flow sensor is the power wire. To do this you will be taking a digital multimeter and using the red probe to check for power. Open your Chevy hood and locate the mass air flow meter, and disconnect the engine harness. Now you will need to insert the ignition key and turn to the “ON” position.
The wire you will be testing is PIN 3 on the ENGINE side of the wiring connector. There should be 12 volts of DC power at this wire. Now check PIN 2 or WIRE 2 on the ENGINE side of the harness to check for a ground signal.
Once you have power and ground confirmed at your Lumina MAF connector, it’s time to check for the signal. In order to test the MAF signal however you will need a digital multimeter, or at least one that can read Frequency Hertz. If your unit does not have the capability to do this, check our link here for the best digital multimeter online.
The wire you will need to measure is PIN 1, but to do this you’ll need to reconnect the engine harness. Once you’ve done so pierce the wire of PIN 1 to get a reading of how much airflow is passing through the Chevy MAF.
Keep your hands, clothing, hair and tools free of the engine, the drive belts and the cooling fans. Now start the engine and read the measurement of the MAF sensor signal wire. This sensor wire should be reading Hz that’s relative to your engine speed. The voltage isn’t the important part of this testing procedure.
At 900 RPM this Hz reading should be steady, without dips or gaps in the voltage. Slowly raise the engine speed and you should see this value rising evenly. Again check for gaps in voltage or spikes in the readings.
If you have any readings that seem outside of these ranges, it’s time for a replacement Chevy mass air flow sensor. Once you’ve corrected or replaced your mass air flow sensor, you can use a OBDII scan tool to clear your check engine code. Have any questions about our guide to testing a Lumina MAF Sensor? Leave us a comment below and let us know!
