The MAF sensor in your Ford is otherwise known as the Mustang Mass Airflow Sensor. The MAF is responsible for reading the airflow entering your Mustang engine. When this sensor is dirty or becomes faulty over time, your Mustang will run roughly. Without correct airflow readings, your Mustang Powertrain Control Module (PCM) won’t know how much fuel to deliver.
There are many common symptoms that can arise from a failing Mustang Mass Airflow sensor. While most of these are simply annoyances or inconveniences, complete failure of this sensor will prevent your engine from starting. Today I will be showing you how to diagnose and troubleshoot the Mustang MAF in a 1998 Ford Mustang with a 3.8 liter V6 in it.
Symptoms of a failed Mustang Mass Airflow Sensor
One of the first problems that can come from a failed MAF is a OBDII trouble code. There’s two common check engine lights that can come out from trouble with your Mustang MAF. If your 3.8 liter V6 Mustang Mass Airflow sensor is sending low reading, the OBDII trouble code will be P0102. This specific verbiage for this code is MAF Signal Low Input to PCM.
The opposite of this error code is trouble code P0103. This is for the trouble code MAF Signal High Input to PCM. Either way your V6 Mustang will run rough and less efficiently because your PCM won’t know how much air is entering the engine.
Test your Mustang Mass Airflow for Power
In order to test this Mustang Mass Airflow sensor, you will need to use a multimeter to read the DC voltage at the wires. If you don’t know what a multimeter is, check out our handy guide here.
Open your hood and located the MAF, which is circled below. This unit is a 4 pin unit that’s mounted under your air intake filter housing and cover.
Avoid expensive repair jobs and entrusting your V6 Mustang to a mechanic, test your Mustang Mass Airflow sensor by starting with the power wire first. You don’t need to unplug or remove the MAF to complete this part of the testing procedure.
To begin locate the RED wire or PIN 1 as it’s labeled in the diagram above. First you must turn the Ford Mustang ignition to the “ON” position to power your engine sensors. Now using your multimeter, check this wire for a 12V DC power signal.
The next wire you will be testing is PIN 2, which is the low reference ground signal wire. This wire is BLACK and should return a chassis ground signal. There is another ground wire on this Mustang Mass Airflow sensor and that one is supplied by the Ford PCM. This is PIN C, and when testing this pin make sure you do not accidentally send power to this wire.
Testing the Mustang Mass Airflow for Signal
The last part of our How to guide to testing your airflow sensor in your 3.8 liter V6 engine is the signal wire. The signal wire for this MAF is PIN 4 which should be a light green colored wire.
This part of our How To Test your Mustang Mass Airflow sensor is a bit more difficult. It will require starting your engine, so make sure you stay clear of your engine and any moving parts. This includes your belt assembly, your power accessories, pulleys and especially fans.
PIN 4 can be pierced by your multimeter, and you will be asking your friend to start the engine with the MAF connected. Make sure that the transmission is in neutral or PARK, and that your parking brake is up. Use all of the proper safety steps to ensure that you are safe and working safely.
Once your engine is started up, you should see about .9 volts of DC voltage at the light green wire. You can manually open the throttle blade or ask your friend to rev your engine to 1500 RPM. At this point you should see 1.2-1.4 volts of DC signal. Increase the engine speed to 2500 RPM and then you should see 1.7-1.9 volts of signal. The actual voltage reading on your multimeter will vary slightly, but the readings should be within this range.
If your Mustang Mass Airflow sensor doesn’t return these values, it’s time to replace your MAF with a new unit. Are you looking to upgrade your Mustang MAF? or do you maybe own a 4.6 liter V8 version of this engine and want to test the MAF? Check our guides below.