How to test a Ford MAF sensor

This is a case study on a 1997 Ford Explorer 4.0L engine with a MAF sensor fault. It also has rich exhaust codes P0172 and P0175.

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[shanestrains]

That's an FF2, Ford Factory-installed 2step. Nice fix, I've been learning so much about electrical diagnostics from you!

[winfoley]

Thanks ScannerDanner - My '89 Ranger 2.3 with 135k restoration project stalled because I couldnt find the problem. Replaced MAF and solenoid a week ago and stalling and hesitation persisted. Dangerous for driving. I put in o2 sensor cause it was totally clogged. Better, but still bad. Did what you said and disconnected MAF and turned ignition on off on off. Wow, runs great! The aftermarket MAF is crap. Will be putting in a Motorcraft MAF tomorrow and I think the problem is solved.

[labradormcgraw]

Brilliant; absolutely brilliant. Even when the rain stops play, the video still ends up being a winner.

[FinalStopMobileAutoTech]

Great video Paul! i noticed that with the MAF plugged in, Both PID's for Pulse width were over 40ms!! And with it unplugged, around the 2ms mark!! Very cool stuff!!

[cesarlopez-ptew]

Man i want to be camera guy for you. I have a great resume, I graduated from holding a flashlight for other techs when i was younger.

[johnwrenchspeed]

Great video. I agree with the grams/second approximate correlation to engine size in liters. This is what I was taught and have observed. However, it is an approximation. As you are no doubt aware, the speed of the PIDs could be increased if you would have gone into a custom setup and limited their number (as we should remember, the PIDs are pushed out by the PCM in series, i.e., sequentially, and repeated over and over).

[ii-ucnr]

Really enjoyed this video, My 98 2.5l ranger has a 0.50 g/s with and without the MAF connected. This is the second time ive had a bad MAF sensor, my first one I broke and this second one lasted me a month before it went.

[andreagili]

Always glad to see you, you are the man! Love you like a bro, respect you like a master. I am studying diesel engines now, but none of the teachers are as good as you, i'm missing your capacity of making student understand, i'm missing you. By the way italian mechanics eyes pops out when they see your book, at least the lazybones :)
God bless

[xerxes]

Nice diagnose as always, have to ad your filming technique is excellent too very good job with camera.

[anthonyminnard]

My 98 mountaineer keeps throwing p0102 cleaned maf replaced maf no matter what I do I read 1.8 to 2.6 g/s and it jumps between the two at idle and stays at 1.8 when I throttle up

[zlatkomustovic]

Can you have any information if you checking maf sensor with ordinary multimeter? Finding problems when you measure wires and connections only with meter?:)

[dedraroberts]

Scanner Danner got a question i have a ford mustang gt and I have a misfire I've replaced plugs and coils and every normal thing you'd I took it to ford and they said my maf is out of range its suppose to be 156 hz and it's running like 148 or is that enough to cause running issues?

[wickedspray]

From what I've heard the grams per second should be roughly the size of the engine at idle and about 40x the engine size at w.o.t. (4 liter engine around 4 g/ps idle and around 160 g/ps at w.o.t). I'm pretty sure these numbers will not work with turbo or supercharged engines though.

[mph]

Would you sell that job plugs and a MAF or just the MAF and the plugs will clean themselves up after running properly?

[xdagasx]

Hi, nice educational, thank you, can you tell me what diagnostic tool you are using and is it still good for europian cars as well ?

[jnarez]

Great job awesome videos keep up the great work. Very descriptive videos. I love your channel best one out there.

[retroguitarmaster]

great video, your brother has been making very good videos lately too

[DJDevon]

7:19 My guess It's adding fuel because the MAF gm/S is telling the car it's flying Harry Potter style with no speed or other input feedback.  Dumping fuel to try to keep the engine running but it's just pegged max rich.  It's got a baro MAP backup according to the PIDs (you show baro). The question is why can't it tell that the MAF is lying using the O2, MAP, TPS, IAT, and other inputs?  Ahh because it's in open loop strategy.  Think you just answered your own question.

[rsvp]

could it also be a bad pcv valve in conjunction?

[jonsimmons]

I used shop rags for my face until I used one that had a long steel wire in it from a machine shop and pierced my eye with it. That's when I went to the blue shop towels .