You're gonna' be surprised just how easy it is to accurately test the mass air flow (MAF) sensor on your 1.6L Suzuki Sidekick (Geo/Chevy Tracker) with a multimeter.
Whether your Sidekick is OBD I or OBD II equipped, you don't need a scan tool for the MAF sensor test described in this tutorial.
Contents of this tutorial:
NOTE: The following article may be of help: 1996-1997 MAF Sensor Wiring Diagram (1.6L Sidekick / Tracker).
Symptoms Of A BAD MAF Sensor
The MAF sensor's role is to help the PCM know how much air is entering the engine so that it can calculate the correct amount of fuel to inject.
This task, of measuring the amount of air entering the engine, makes the MAF sensor a crucial component of your Sidekick's engine management system... so when it fails, it wreaks havoc on your Sidekick's engine performance.
Here's a list of the symptoms you'll see with a failed MAF sensor:
- If your Sidekick is OBD I equipped, you'll see one of the following diagnostic trouble codes (DTCs):
- 33: MAF Sensor Circuit, Signal Voltage High.
- 34: MAF Sensor Circuit, Signal Voltage Low.
- If your Sidekick is OBD II equipped, you'll see one of the following diagnostic trouble codes (DTCs):
- P0101: MAF Sensor Performance.
- P0102: MAF Sensor (MAF) Low Input.
- P0103: MAF Sensor (MAF) High Input.
- Doesn't pass the smog check.
- Engine idles rough.
- Engine takes forever to start (extended cranking time).
- Engine doesn't start.
- Black smoke coming out of the tail-pipe as engine runs.
Let's jump into the first test in the next subheading...
TEST 1: Checking The MAF Sensor Signal
The key to diagnosing a bad MAF sensor is to know that its voltage signal increases with increased air flow (like when you step on the accelerator pedal) and decreases as that air flow slows down (like when you step off of the accelerator pedal).
With a multimeter, we can tap into the MAF signal wire and observe theses voltage changes as we rev the engine up and down. The wire that carries this signal is the gray with black stripe (GRY/BLK) wire of the 3-wire MAF sensor connector.
NOTE: Be careful and take all necessary safety precautions! The MAF test in this section is done with your Suzuki Sidekick's engine running.
NOTE: The connector in the illustration above is the connector on the MAF sensor itself and NOT the engine wiring harness MAF connector.
These are the test steps:
Set the multimeter to Volts DC mode and probe the GRY/BLK wire of the MAF sensor connector with the red multimeter test lead.
The GRY/BLK wire is the one that connects to MAF sensor pin 3 in the illustration above.
NOTE: You'll need to use a tool like a wire piercing probe to access the signal inside the wire. To see what a wire piercing probe looks like, go here: Wire Piercing Probe (at: easyautodiagnostics.com).
Ground the black multimeter test lead directly on the battery negative terminal.
Have a helper start the engine. Wait for the engine's idle to stabilize and observe your multimeter's voltage reading.
With the engine idling, the voltage reading should be about 1.5 to 1.8 Volts DC.
Now, have your helper accelerate the engine. The voltage should increase.
At around 4,000 RPMs, the multimeter should register to about 3 Volts DC.
Decelerate and accelerate the engine several times as you observe the multimeter
Your multimeter should register a decrease/increase in voltage as you decelerate/accelerate the engine if the MAF sensor is good.
If the MAF sensor is bad, the voltage will be stuck at a certain number no matter how much you accelerate/decelerate the engine.
OK, let's take a look at what your MAF sensor test results mean:
CASE 1: The MAF sensor produced and increasing/decreasing voltage signal as you accelerated/decelerated the engine: This tells you that the mass air flow sensor is OK (not defective).
CASE 2: Your multimeter registered voltage, but it did not increase or decrease as you accelerated/decelerated the engine: This confirms that the mass air flow (MAF) sensor on your 1.6L Sidekick (or 1.6L Geo/Chevrolet Tracker) is BAD. Replacing the MAF sensor will solve the MAF sensor trouble code lighting up the check engine light.
CASE 3: Your multimeter registered 0 Volts: This usually means that the MAF sensor is fried. To be absolutely sure, I suggest confirming that the MAF sensor has power and ground. If both (power and ground) are present, the MAF sensor is BAD. To test for power, go to TEST 2: Verifying The MAF Sensor Is Getting Power.