How To Test The Ford MAF Sensor (4.2L, 4.6L, 5.4L)

Testing the MAF (Granddonkey Air Flow) sensor on your Ford truck or SUV or full size van is a very simple and like shooting fish in a barrel thing. This article will walk yous through the whole process without removing the MAF sensor from the engine. As you may already know, the MAF sensor is inside the round air filter canister assembly and this article volition teach you how to test it.

The MAF sensor test/diagnostic tin be achieved in four piece of cake steps using a multimeter. You don't even demand a scan tool! Below y'all'll find of import pre-test info that'll speed upward the diagnostic process.

If you lot're looking for the article on how to examination the Ford MAF sensor that's non inside the air filter canister assembly, go here: How To Test Ford MAF Sensors Using A Multimeter.

OK, one last thing before we jump into the test, if you're diagnosing a 4.6L or 5.4L choice up or SUV, let me just make you lot aware where you can find a complete list of 4.6L and five.4L 'How To Exam' manufactures that are located in this Web Site and at troubleshootmyvehicle.com and this list is constitute hither: Ford 4.6L, five.4L Alphabetize Of Manufactures.

En Español Yous tin can find this tutorial in Castilian here: Cómo Probar El MAF Ford (iv.2L, iv.6L, 5.4L) (at: autotecnico-online.com).

Common Symptoms Of A Bad Ford MAF Sensor

This list covers the majority of symptoms I've seen on these types of Ford mass air menstruation sensors:

  1. MAF Codes that light up the bank check engine light (CEL) on your instrument cluster.
    1. P0102: Mass Air Flow (MAF) Circuit Depression Input.
    2. P0103: Mass Air Flow (MAF) Excursion High Input.
  2. MAF sensor malfunction that DOES NOT lite up the check engine low-cal (CEL).
  3. Lean and/or Rich code(south).
  4. Fuel Trim code(s).
  5. A tremendous lack of power upon acceleration.
  6. Black fume coming from the tail-pipe.
  7. Bad gas mileage.
  8. Vehicle may idle rough and stall.

Is My Ford MAF Sensor Just Dirty?

Is My Ford MAF Sensor Just Dirty? How To Test The Ford MAF Sensor (4.2L, 4.6L, 5.4L)

MAF sensors take a tremendous tendency to go dirty and cause several headaches that may include: bad gas mileage, higher emissions, and/or lack of power. For the nigh part, when one is muddied, the truck, or van or SUV seems to drive OK, merely not with the same peppiness every bit before. And then how practise I diagnose a dirty/contaminated Ford MAF sensor? Well:

  1. I'll take a quick await before I start my diagnostic and see if the ii hot-wires (that make up the MAF sensor) are dirty. By dirty I mean 'contaminated' (to use an industry standard term). To see an example of this: Dirty MAF Sensor Case.
  2. Or, I'll test it showtime following the guidelines gear up in this commodity, to see if it'southward producing a MAF signal.
  3. If it is producing a point, but the signal'south response is also slow to changes in throttle position, then I know to look into cleaning it.

Why does it become dirty/contaminated? Well, it'due south usually due to an air filter not performing its chore or the round plastic canister assembly, that holds the air filter, is broken or not sealing correctly. The Ford MAF sensors are some of the easiest MAF sensor to make clean. To see/read the step by step instructions on how to clean this type of Ford MAF sensor in the round air filter canister, click here: Cleaning The Ford Canister Blazon MAF Sensor.

Checking The MAF Sensor Hot-Wires For Contamination. How To Test The Ford MAF Sensor (4.2L, 4.6L, 5.4L)

Air Leaks Wreaking Havoc On MAF Sensor Control

The second most common problem I accept encountered on almost Fords (Mercurys and Lincolns) over the years is air leaks betwixt the MAF sensor and the throttle trunk. It is crucial, aye very disquisitional that y'all first cheque that at that place are no air leaks between these two. Air entering after the mass air flow sensor into the engine will negatively impact fuel injection. And will skew the results of your tests which could event in the replacement of a expert MAF (and in the process throwing money away).

How do you cheque for air leaks? With your eyes and hands. That's right, no special tools required. Merely eyeball and physically shake/move the rubber air ducts that connect the MAF sensor to the throttle trunk to see if it's loose or disconnected.

Excursion Descriptions Of The Ford MAF Sensor'due south Connector

Circuit Descriptions Of The Ford MAF Sensor's Connector. How To Test The Ford MAF Sensor (4.2L, 4.6L, 5.4L)

Whether your driving a Ford, Mercury or Lincoln full size pick up (F150-F350), SUV, or full size van (E150-E350) the circuits descriptions of the wires coming out of the circular air filter canister are the aforementioned. You'll notice that the photos (in the image photo above) accept the MAF connectors numbered 1 thru' 4. I'll be using these numbers for the circuit descriptions. Here's the description of each circuit beneath:

  1. Number ane:
    1. MAF Signal.
  2. Number two:
    1. Ground that the ECM provides.
  3. Number 3:
    1. Ground.
  4. Number 4:
    1. 12 Volts.

To test these circuits you'll need to use a tool to pierce the wire to be tested. I recommend using a wire-piercing probe since it'll be the most effective and easiest way of getting to the point. If you need to see what this tool looks like, click here: Wire-Piercing Probe. Independent of the method you use, be careful not to harm the wire(s). Take all prophylactic precautions.

Some other important matter to note is that the colour of the wires (coming out of your Ford, Lincoln or Mercury pick up or SUV or van) does non thing. In other words, the circuit clarification/job of the wire is the same regardless of Make/Model and color of the wire.

Important: All of the tests are ON Auto TESTS, practise not remove the mass air flow sensor from the vehicle or from its plumbing.