Diagnosis and Understanding: MAF Sensor Pt1 Analog, Digital, Hotwire, P0101 P0102...

It's back to the DEBOK for the most comprehensive tutorial on the MAF sensor you'll find.
Become an expert in air induction diagnosis with this video!
Part 2 is here: • Diagnosis and Understa...
Other videos on my channel on induction and stoich maintenance:
Fuel Trim: • Secret of Engine Probl...
MAP Sensor: • MAP Sensor Diagnosis a...
TPS Sensor: • TPS (Throttle Position...
Air Fuel Sensor: • Air/Fuel Wideband vs O...
IAT Sensor: • IAT ( Intake Air Tempe...
IAC (mentioned): • P0171 Case Study from ...

[@tomthumb3085]

Absolutely on point explanations. First class educational video, just what is needed on KZbin. No techno babble, no pie-in-the sky theory, just sound detailed advice.

[@LeewardStudios]

As a friend once said, there are plenty of parts swappers in the world but few true mechanics. You sir, are a mechanic. Thanks you for the education!

[@SchrodingersBox]

Thanks 👍

[@danthecarman1090]

I'm in awe at your ability to explain all of this so clearly. Thank you so much and please - keep these videos comin'!

[@SchrodingersBox]

+DanTheCarMan Thanks man! there will definitely be more videos!

[@TheYO7A]

There are zillions of youtubers with their massively edited useless videos and on the other side there is this boy who is killing it with a micro white board and pen

[@SchrodingersBox]

hahaha thanks man!!!

[@threadtapwhisperer5136]

Aint that the truth. I told my dad about the wonders of DIY videos and the horrors of the same "hey, heres 45 minutes of my life story and a camera angle of the floorboards, good luck getting to the info" type of videos. Therezs a channel of all 2-5minute MAX home appliance diag and repair videos. They straight up tell ya "this video covers diagnosing the stove heater pots, go to video X in this playlist for how to remove the panel." Then just BOOM, right into the info you seek. They are my heros. Also, that was Dads first full irate into tranquil repair and DIY Internet info searching project. Old dog, sure, but hes still got some new tricks..😂 Wish I could remember the channel, at the moment. They are so good, ya just sorta get your info and move on. If I can find it in my 1000 plus subscribed channels, ill try to edit it in here. Edit: AppliancePartsPros is the youtube channel. "

[@mrghiax]

If only more people (including many professionals) would watch your diagnosis and understanding videos they would really up their game to another level! To be honest Matt all of your diagnosis and understanding videos on engine management systems are the best on these subjects. You have a unique teaching ability that even diyers can easily understand. Such a shame that more people do not take advantage from what you are offering ...

[@SchrodingersBox]

Thanks man! Good to see you back by the way!

[@projektaielektrotechnika3654]

@@SchrodingersBox hello. Could you give me adwise what could be with my car. Somethimes it starts jerking when i am driving ( sorry for my english). It is diesel car. After scan. There isnt any error.

[@hondagamer79]

@@projektaielektrotechnika3654 sorry idk about diesel engine but it's looks like miss fire... well I think you fixed it bc the comment before 3 years ago..

[@helgikristjansson4702]

Dear Matt. Thanks for all the fantastic videos. I have watched 1000´s of hours of Automotive DIY videos on KZbin, but I find your videos the most informative, and I love your scientific approach. Many thanks.

[@SchrodingersBox]

Wow, thanks!

[@BonBonShrimp]

Just 4 minutes in, and subscribed. As an engineer (but very illiterate about cars), your style totally resonates with me. I'm hoping this video will answer my questions about my car's bad MAF sensor that I am currently dealing with, so I can make an educated decision.

[@SchrodingersBox]

Great to hear!! People like you are exactly the target audience I am aiming for!!

[@findvoltage]

I realy would agree that your video of fuel trim is by far the single most fascinating of all on thr internet. So simple, yet so very complex. Awesome, just a brilliant upload.

[@SchrodingersBox]

findvoltage Thanks man. This is still my favorite video by far on my channel. Maybe 95% of engine performance diagnostics start with or involve fuel trim analysis.

[@abusaad1286]

The best car video channel on youtube Matt, I learned many things from your videos about sensors & many other things which you always talking about in middle of your videos, I'm not a mechanic, just an ordinary guy who like cars & watch you from Saudi Arabia, Big like & big thanks Matt, You are the best ...

[@SchrodingersBox]

Thanks man!

[@heavyhaulingequipment2611]

My New Favorite Chanel , Absolutely a wealth of knowledge on how the sensors operate & Correlate with each other And the proper way to diagnose my Vehicle, THANK YOU Matt !!!!!

[@SchrodingersBox]

Wow, thanks! Glad you found me!!

[@techatozdev9019]

Love the way u explain things in very simplified way and quick to understand We need good people like u in our society. Thanks Matt

[@SchrodingersBox]

It's my pleasure!

[@POOKIE5592]

You make fantastic videos for us DIY guys who don't want to pay someone $100 an hour to guess and throw parts at our car. Thank you very much!

[@cambercrtr3004]

This is an absolutely fantastic video and education! When you have a great teacher its incredible how exciting the learning experience can become for the student and how far they might go. What a great feeling it is to truly begin to understand how things really work! THANK YOU for taking the time to teach us as you do!

[@jeremyhenges5783]

There really ain’t words that say holy shit thank you enough! Your fuel trim vids are enlightening at the very least. I’m sold on your channel, 5 thumbs up!

[@SchrodingersBox]

Thank you! I try to keep a high standard for content here lol.

[@Watchershing]

Love this brother. You have gotten to the foundation of the matter with the meter readings. Actually it got me thinking about the nature of reality and how we can have very different experiences as individuals as we look and seem to be the same. But that is for the other channel. 😊 Enjoyed your presentation.

[@s.alexis1599]

Thank you for your Diagnosis and Understanding videos. Your explanations are really clear even for a French who don't speak english fluently.

[@cody9419]

Good shit! I heard a woman on a video on your ch. call you 'Mr. Molecular Biologist!" You must be a prof. What do you study? I'm SO glad I came upon this resource. I'm brand new to autos. I was a research tech. in Biomed. @ Pitt. I've learned SO much compared to any other auto vids. I've watched. And, I've only watched 4 so far!. Thanks, again. Looking forward to it!

[@hayzersolar]

Thanks I spent 400$+ on my car for codes at AutoZone and watch your fuel trim videos and bought a 120$ Bosch scan tool and found out it was a intake leak and not ant of my sensors but now I know thanks to u

[@roundcornerent]

You're the best man ! Real teachers / instructors, should be jealous .

[@Micscience]

Before I move onto part2 I just want to let you know Matt that I appreciate what you are doing. I like how you are getting at the fundamentals. I have always learned best by getting a good grasp of how something works and then the troubleshooting just comes naturally in my case. Like Danthecarman said your explanation, the way you break it down is spot on and it makes it so much easier. I was going to join the scannerdanner monthly subscription and I still may, but for where I am at as far as knowledge right now, I think your channel is going to help me out more. I'll soon be joining your monthly subscription. Take care!

[@SchrodingersBox]

+Micscience Thanks man, most people don't see what I try to do. In all fairness danner's pay channel is excellent and I have many, many people tell me they watch my material to actually help them understand Danner's material (not my intent but I can see how that might be a consequence of my channel). I suggest the free trial on danner's channel and watch a few videos- then watch my pay channel videos on similar topics (cam and crank sensors for example)- then REWATCH the videos from Danner's channel. You will most likely end up subscribing to both channels lol.

[@oliverrojas7117]

Thanks for this analysis. II ended up replacing the MAF Sensor to no avail. Your explanations video help demonstrate how a trouble shooting diagnosis procedure can improve. The symptom was the engine turning and starting before shutting right off. Unplugging the Mass Air Flow Sensor made the 3.3 GM V 6 run okay. At some point I looked over everything I touched when trying to figure out how to access spark plugs for cylinders 1 3 and 5. Upon doing so I noticed a loose bolt that was securing a vacuum source that I learned to identify after referencing the service manual. The following day I heard a hissing sound and found a broken tube that connects to the evaporator canister. I used electrical tape to help provide a seal to the bolt attached to the vacuum source since i over torqued it and bent the piece inward. Then I used electrical tape to help secure the vacuum hose leading to the evaporator canister. The car finally starts up and idles okay. Now there is a DTC 22 (Throttle Postion Low) that I am waiting to see if it goes away after driving and re- learning by the computer now that there are little to no vacuum leaks.

[@SchrodingersBox]

Just simply Check the fuel trim to confirm if the vacuum leaks are gone.

[@labradormcgraw2409]

Got an issue with a MAF sensor on my Ford, so I kicked off by searching for videos on MAF sensor testing. What was I thinking? When will I learn that, for proper diagnosis of engine faults, there's really only one guy. Ok, ScannerDanner is good, but this guy takes the biscuit. It almost seems ironic that the best automotive teacher on KZbin is also the most under-rated. Forget the others, just filter your search results to include only those from Schrödinger's Box.

[@luclucas135]

Guess im the only non advanced diy mechanic who listens to this but this is awesome, thanks !

[@stseely1]

FYI. It's not necessary to have an oscope to read the frequency signals. A fluke 289 will read the frequency, amplitude and duty cycle and even read PWM all on one screen in numerical values. Not as good as an oscope. I have an oscope too but it's AC powered with I think tends to induce unwanted noise into the trace. I would like to get a snapon modis. Love the videos, great job.

[@alscouten8700]

great video. Ive met alot guys who don't understand the science and logic behind it all. they just know how to swap various parts out quick enough to make the boss happy. they don't even wanna touch it. might hurt they're heads from to much thinking

[@OscarSegundo]

These are the kind of videos I like. Very informative, reminds me of A/C Tech School.

[@SchrodingersBox]

Oscar Segundo These are the kinds I like too, and the kinds I learn the most from myself. They are pretty rare- most people will just disregard a video over 3 minutes in length lol

[@Beyond-Repair]

I am an auto repair professional. I was using your very informative MAF videos to help me with a particular diagnosis. You talk about 3-wire, 4-wire, and more sensors. I have made an image for a MAF connector for a 5-wire MAF on the VW Jetta I'm working on. The pinout works like this: PIN #1: IAT SIGNAL; PIN #2: B+ FROM FUEL PUMP RELAY; PIN #3: ECM LOW REFERENCE (-); PIN #4 VREF ECM +5VDC; PIN #5: MAF SIGNAL. I can't offer the image in the comments, but I can offer it to you if you like.

[@SchrodingersBox]

sure I would like to see it. [e-mail]

[@Beyond-Repair]

This is a fairly common configuration for integrated MAF/IAT sensors.

[@RickyPisano]

There IS no easy way around it. But the time you take to watch these videos will give you an understanding of how these modern engines run. It will also save you a ton of money buying parts YOU DON'T NEED and actually zeroing in on the cause of the problem. I.E... the CHECK ENGINE light comes on. An error code trips it.... could be an O2 sensor. But it doesn't mean the O2 sensor is bad necessarily. There are many reasons an O2 sensor will send an error code. This applies to many other sensor and codes also. This is the value of Matts videos. If you LIKE buying parts you don't need, chances are good you'll be gone in 5 minutes. But believe me man....I used to do EVERYTHING on the old pre-ECM engines. Early '80's. V-8's, Slant 6's, Straight 6's, 4 bangers. Could do anything on them. Blindfolded. Then....I lost my garage due to divorce moved to L.A. I didn't open a hood in 2+ decades. In 2017 I bought a 2005 500 Limited with the 3.0L Duratec DOHC V-6. When I opened the hood I didn't know what I was looking at. It was a WTF moment FOR SURE!! But I knew, bottom line, it was still AN ENGINE. I bounced around KZbin, watched lots of "HOW TO" videos and bought parts that did NOTHING. Cleared the Check Engine Light and thought I was good. A few days later the light would come back on WITH THE SAME CODE!! So frustrating man. Then, thankfully, I found this channel and learned more than I could ever tell you here and I still am. But I'm not intimidated by these engines anymore because of Matt. Doing my own work again and come back often for refreshers. The best automotive channel on KZbin HANDS DOWN on understanding the WHY instead of the HOW to do a job. A huge difference. Thanks A MILLION buddy!!

[@SchrodingersBox]

Thanks for the great comment. You totally get it man. Congratulations and happy diagnosing!!

[@freeryder4891]

Automobile systems mastery training. Like a boss! Thank you sir!

[@YoucefKhetib266]

Man, you are a national treasure !

[@SchrodingersBox]

Hahahaha a national treasure omg lol!!!! Too kind of you.

[@jgeorges3061]

now I know what is the different between the analog and digital signals and how to understand each one, Big thank you matte now I am going to watch part 2.

[@SchrodingersBox]

j georges Part 2 is a good application for Part 1. Even I get thrown a curveball 5 minutes in lol.

[@indeepatv_6169]

Hey Matt, I'm new to you're channel. Watched a couple videos and plan on watching the rest. Great extensive knowledge. Awesome how you go in depth and make it easy to understand. Good attitude good videos keep up the great work! You the man

[@SchrodingersBox]

Glad you found the channel!

[@icepick859]

I got one im my shop i wish you could go through. 2016 mazda 6. P0171. Ltft is stuck at 20.3 and stft 10+ the fuels trims stay this lean at idle and when increasing throttle, they are always like this. Low side Fuel pressure is good (65psi at idle), high pressure fuel pump is good (actual vs desired right on spec), all input sensors are good with normal readings, no vacuum leaks, pcv system is good, purge valve is good not stuck open causing more vaccun. I ran it on fuel injection machine in the fuel rail to eliminate bad gas or something, fuel trims stayed the same. AF ratio sesnor is good, maf has been replaced with factory maf, no change, always reads in spec. Vehicle has a map sensor also, readings from that are on spec also. Im at a complete loss at this point. Oh the fuel injectors are very clean, as seen with boroscope, as they should as I ran fuel injecton cleaner through it. I don't know what to do at this point....

[@SchrodingersBox]

what happens if you induce a rich condition on the engine?

[@icepick859]

I dont have a propane injection tool so the only way I can introduce a rich condition was by spraying throttle body cleaner directly into throttle body. For the short time I could do that before killing the engine the stft did go negative for once. that was only time I ever saw the stft ever go negative while running this car. When I reset the fuel trims by clearing the KAM, the stft just climbs to max and it actually runs pretty bad while it's learning the fuel trims, rough idle, stuttering and then once ltft hits 20.3 and stft go back to 10-15 ish it runs pretty good. No loss of power or rough idle. But still sets a lean code cause of how high the correction is

[@SchrodingersBox]

What do the oxygen sensors show if you drive the car at WOT?

[@icepick859]

@@SchrodingersBox when driving and going WOT the O2 goes lean. Fuel trims stay at 20 ltft and around 10-15 stft. On decel the stft will go to 0 and ltft stays at 20.3

[@SchrodingersBox]

Ok that’s a huge clue. At WOT a car should always run rich. Your O2’s should max out rich. If they do not they you have one of two issues- either insufficient fuel delivery OR undermeasured induction. Those are the only two possibilities.

[@henrybikeman]

The people who come up with these ideas are.............engineers! I are wun! Good teaching sir.

[@DJDevon3]

Most common DVOM's will only do 1 second refresh rates (1 Hz). That means you can only have 1 signal change per second. Any faster than that and the DVOM is no longer reliable and only an oscilloscope will be able to measure the digital signal. Understanding electronic concepts such as frequency, amplitude, and modulation is crucial in understanding the limitations of using a DVOM on things like a digital MAF or O2. Comes down to the right tool for the right job. You wouldn't use a screwdriver where a sledge hammer is needed right? Brilliant video so far. Really enjoying this.

[@SchrodingersBox]

***** Is that right? Only 1 Hz? I had no idea... I thought maybe at least 10 or 20hz but thats crazy! Man How in the world did I live with only a DVOM all this time lol!!

[@DJDevon3]

Schrodingers Box It can vary depending on the DVOM. More expensive top of the line Fluke meters can track frequency around 400Hz. Most common cheap meters (under $100) are only 1Hz yes. They are designed for measuring voltage not frequency. Frequency is a premium feature. I think more specifically it's like .98 of a second or something like that. Close enough that it's basically 1Hz yeah. That's why they're so cheap compared to Fluke's and other meters with advanced features.

[@SchrodingersBox]

***** Lol, you are to DVOM's what Danner is to the Verus lol. I never even knew any of that. All I know is Fluke looked like a gyp at $400+ lol. Now it makes sense. I always thought I was expected to pay for a name and the ability to keep the high/low reading lol

[@DJDevon3]

Schrodingers Box There's certainly brand cost like Apple associated with it. You are right about that but it does have more valuable and powerful features. The line conditioning inside the meter is much tougher too. Quality components.

[@DJDevon3]

Schrodingers Box I'm definitely not that good with DVOM's. I know more about them then how to actually use them lol. You are probably better with them than I am. Seriously.

[@seshachary5580]

very educative. Thank you regards

[@SchrodingersBox]

Thanks for watching!!

[@Autofixpals]

awesome explanation. You should explain how the MAF produces the 1-5 volt signal back to the ECM in relationship to air flow past the Hot wire.. You explain how the Hot wire receives varying current to maintain a certain temperature via the 12v wire. But what does the 5v reference get processed with in order to send the relative signal back to the ECM?

[@hammadmadi4285]

Man u Are Mechanincal Professor Respect From Pakistan

[@latinman9791]

This guy is an awesome teacher professor!!!

[@SchrodingersBox]

Wow, thanks!

[@sreenivasanm4303]

Great video with excellent and comprehensive explanation. My thanks and appreciation.

[@paulmarian5570]

It's a mistery for me how a man so smart, and who can talk so rapidly, and without verbal mistakes, can have such a bad writing. 🤣. Anyway, thank you for all new things that i am learning from you every video!

[@SchrodingersBox]

Hahahah. I have heard all my life about my terrible writing and horrific drawing ability. I guess I am just 100% left brain and no right brain lol

[@basketballmove9172]

You're a good teacher Matt. Your explanation was clearly and easy to understand. Thanks for information sharing I hope you're getting well.

[@2abmw]

i found that the vaf sensors are quite reliable (i think i replaced four in 28 years, three had bad fuel pump switches, never had problems with carbon build up) i think the biggest drawback is slow response time and i suspect they are more expensive to manufacture.

[@atomicdmt8763]

thanks for this VIDEO! It seems a faulty/aged MAF sensor is creating a random P0300. I cleaned it initially- but finally just installed a new one yesterday and the performance is appreciable. Less $$ than I thought. DIY.

[@abderrahimmark]

I cameback to rewatch this after your recent MAF videos. There is nothing that scares me more than not knowing what the maf reading should be. In diesel they operate differently, I guess.

[@SchrodingersBox]

Yeah I used to think the same actually- “what should the MAF read?” But what I’ve learned is that on an analog MAF- all that matters is the voltage. If the MAF voltage is not at least 4V at WOT- there’s a MAF issue. That’s all that matters. Now on a digital MAF you can’t really do that so it’s definitely more of a challenge.

[@JSWMobileMedia]

Killer video! Great info with detailed explanations that I could actually keep up with! Thanks!

[@DENicholsAutoBravado]

Anyone else catch that he introduced himself as MAF? Nice Freudian Slip...not a true one, but the phrase has slowly changed to mean that something you're mind is working on came out. So cool. :) Purposeful or not. Spoiler alert didn't ruin anything. As you hinted at 7:20 about about another non scan tool test I was all smiles. :)

[@SchrodingersBox]

DE Nichols Hey DE- send me A PM your next chance.

[@nandanalal5072]

Your english is very clear,keep it up

[@SchrodingersBox]

Thank you! It’s funny but I get this comment a lot from people who don’t speak English as a first language. They all say my clear and correct use of English helps them understand the material better. I consider it a great compliment!!

The frequency can be easilly be measured by your ear with small speaker connected thru 1k/10k resistor. You will simply hear the frequency. This is usefull for those who doesnt have an osciloscope.

[@adriem2104]

+Tomáš Kamenický (ViaExplore) Thank you ! I will try this. It's an interesting idea ! Wow. The speaker thru the 10k resistor and the ground ,i think.

[@johnmwangi6291]

Interesting idea

[@enriquev8832]

Wow!! Amazing!! I’m hooked on your videos

[@SchrodingersBox]

Awesome! Thank you!

[@nilhansilva7247]

Your vedios are very useful to me in diagnosis. Thanks a lot

[@SchrodingersBox]

Glad to hear it!!

[@adriem2104]

Thank you !!! You are amazing good to explain theese things. From this video i finaly understand why, in my Peugeot 207, the MAF voltage was 2,5v compare to the ground and 10v aproximatively compare to 12,5 Volts of battery. Because is a Frequency MAF. I have installed a kind of device for controlling some sensors , for increase the mileage.( That's because i have installed a HHO Hydrogen cell on my car ). Now i will try to connect that device to MAP sensor and the second IAT sensor who are near the intake engine. ( it is the first IAT, near the MAF , after the air filter) . First i will verify if the MAP have a voltage output... I can't find the Oxygen sensor(s) in this car. Or maybe they don't exist. It's a Peugeot 207, 1600cc , 110 HP , Turbo-Diesel , 2006.

[@geojor]

you've enlightened a lot of viewers, thank you...

[@paulwilliams8763]

Very great presentation. More mechanics need this kind if training especially in my country. Very few goes to school or have formal training. Your at there mercies and when you do find a good mechanic you have to pay through your nose. Thanks for making theae video.

[@kevinkerr8310]

@Renee Redwood I’ve been a mechanic for 42 years and want to be an electrician, you would not work for the wages we get , ps all this shit on motors is why they are never out the garage

[@hinojosa552]

Very well explained , i love it. Love all your videos .

[@NabilChouchany]

Hello Matt!! Excellent stuff!!! At 6:22 the engine does not maintain stoich. at all times, it runs lean at decel, rich at WOT and most vtec and direct injection engines work lean at partial loads low rpms... In fact the more advanced the engine, the less time it operates at stoich and homogeneous combustion (as lean modes require stratified mode as you most likely know)... Just a thought! Cheers!! PS: i'm inclined to watch the fuel trim video (it is the best) with my classroom... will give you feedback if i do so...

[@FaizanAli-qk1mr]

Sir u r more than a professional. Pretty clearly elaborated all the possibilities. That's really wonderful actually Goodness me your energy level is absolute remarkable more than a Boss

[@johnswiecki]

Such a great explanation. Thank you so much. I can’t wait to see part 2.

[@SchrodingersBox]

Glad it was helpful!

[@retamar717]

love your knowledge skills wish there were more techs this way that could help me. i could really use you input on my car issue .

[@mohamedbherey8652]

u reminded me with my first lesson in telecom engineering 🥰 now im studying mechnical

[@josephfaro380]

I'm an ASE Master Certified mechanic and I think your videos are great. Let me know when you come out with a box set

[@SchrodingersBox]

No box set but I have a website with more videos at www.schrodingersboxqm.com

[@arthurfricchione8119]

Awesome videos. Will watch and study all of them. Love knowing how thing work.

[@lizardking8388]

Some voltmeters can measure frequency and duty cycle.

[@johnlong6320]

I enjoy all of your videos. Very informative and helpful. Keep it up

[@josephmythen9357]

I just cleaned my MAF by removing it and and spraying it with CRC electronics cleaner and no wiping or touching the wires on a Ford Windstar 2003 model with a 3.8 engine and the difference in idle was dramatic in a good way. I had just within the last month replaced the head on the front side of the motor because of a burnt and leaking exhaust valve , the idle after the head replacement was good but not right. Eventually the engine light came on (after 500 miles) and I got a code of PO 174......I would suggest doing this cleaning before replacing the MAF itself as they can be pretty exspensive...instead I spent nine dollars for the spray from CRC which leaves no residue.....The sensor is the first to affect engine idle ...and if it doesn't solve a rough idle you can move onto oxygen sensors or gasket/PVC leaks etc... in my case it was dirty wires on the MAF...just an option for you all

[@SchrodingersBox]

How would a dirty MAF cause a P0174 but not a 0171??? What was your STFT and LTFT showing before and after? That is not possible.

[@Red_dot_randy]

Thank you!!! Very easy to understand and I have a hard time learning.

[@SchrodingersBox]

So do I actually.

[@MrYaatri]

Max has the right idea but I think the explanation is slightly off. I would say that square wave pattern will change. At higher air flow, the MAF would have to be supplied hear for longer higher voltage would be sent to MAF for longer duration and for less flow, for shorter duration. So the shape of the square wave would change. I would guess that the frequency would be the fundamental frequency of the fourier series or FFT of the wave form. Thanks for bringing great videos Max

[@carstechno2689]

your presentation is very good ..thanks

[@jacobhendrix6702]

I just solved an issue that was being caused by the MAF not having a screen in front of the sensor. I have a K&N intake system but they don't put the screens in them. Car was running poorly at light throttle. I remember that being mentioned here so I bought a piece of aluminum honeycomb material and made a screen for it and the problem went away. Thanks for the video.

[@paulmvn5431]

my multi-meter has several added features for measuring: Auto-range, Temperature, Frequency, testing Diodes... I got it as a gift, but I think it was fairly expensive.

[@SchrodingersBox]

Paul MvN Yes I have seen those but out of my price range for sure. Gosh I so seldom need anything other than V,A and Ohms I just can't justify the cost, especially now with my Vantage.

[@M.Kursat.B]

Dear Matt Many thanks for your afford and the informations you shared with us. I have been searching the net for a long time and I haven't found the detailed and well structured infos like you share. Please add some about diesels especially. Since I am driving a Ford Kuga (MY2013/ 2.0 tdci AWD) and having troubles with hesitation at low rpms (like after giving a way in a roundabout) Again many thanks

[@DCGGT2000]

Great videos, keep up the good work.I have enjoyed every one !

[@jorgemunoz8881]

Hello, thank's a lot for sharing your knowledge i really appreciate it you had teach Me so much in a so simple way that i have become a much better diagnostician thank's to you keep up the good work blessings!!!

[@SchrodingersBox]

jorge muñoz Thanks Jorge, I will continue doing this

[@elcues]

I have a 1996 Olds.Lss 3.8 Super Charged.My sensor has three wires. Ign.on only. 12vpin-Gnd Pin-2.5v Pin. No 5 volt wire. Engine running the change in the 2.5v pin bounces between 2.5 and 2.6 never goes past 2.6v.. So if the system is digital will you read any difference in voltage on the reference wire. With the engine running. Are you saying the analog meter will not read anything at all with the engine running if the signal is digital. Still fuzzy here! I have a Chilton manual but it has nothing for testing any sensor problems. Nice video, you are a devoted informer and greatly appreciated by many I am sure.

[@SchrodingersBox]

You will possibly see a change in the average voltage but it will not necessarily be dertectably proportional to airflow. On a digital sensor you really need to measure Hz, not voltage.

[@DJDevon3]

Hot wire MAF is actually a resistor that gets energized and the resistance value changes upon heat dissipation from incoming air. Probably a thermistor same as the coolant temp sensor? I'd be interested to see a MAF dissected.

[@SchrodingersBox]

***** Agreed

[@amarabdelli487]

Fantastic video, thank you

[@jawojnicki]

LMAO! What's the frequency Kenneth, is your Benz a dream? Phenomenal song reference! Love your vids even more now. Keep up the vids AND the pop culture refs please.

[@SchrodingersBox]

Lol they go over the heads of most people! Glad to see you and maybe one other guy caught that lol!!

[@rhkips]

Another great video with lots of good information! I haven't run into one of these vortex sensors yet; looks like I'm gonna have to do some research! I think I might have heard something about their existence in passing several years ago, but that's it. On an interesting side note, your mention of O2 sensors reminded me... Pick up an old (or new) analog voltmeter! I think Harbor Frot still sells them. Scopes and GMMs are nice and all, but sometimes it's easier to just toss an old analog meter on the thing. It's definitely cheaper, especially for the DIY guy that doesn't want to drop $1,000 on a low-end scope. :)

[@SchrodingersBox]

Just for fun I put a analog DMM on the MAF after the video just cuz I was curious and it read exactly the same as the digital DVOMs.

[@rhkips]

Schrodingers Box Yeah, I would expect as much. MAF frequencies are just too high for the physical mass of the needle and assembly to respond to. They tend to do well with O2 sensors and various other sensors too, though! :)

[@scottyakoubian9238]

I haven’t heard about “Kenneth“ and “what’s the frequency” in YEARS!!

[@steveneumeyer681]

awesome REM reference

[@Mr.G626]

my 05 silverado threw the code P0102 so i immediately went out and bought a new one...just kidding haha. surprised i missed this video.

[@MrJulgrc75]

You are good teacher thanks to share God bless you

[@georgebonney90]

i really appreciate videos like this,thank u sir

[@orinjackson6446]

Very good video. Thanks

[@luxurycarpets4028]

Appreciated 👍 very well done and good explanation very simple and to the point . I have a problem if you can help me out please , It’s a Range Rover sport 2010 3.0 diesel. 1-Starts straight away 2-engine light is on and it’s on limp mode 3- throwing code p0193 4-change the high pressure fuel rail including the sensor 5-changed map and maf sensors 6-car won’t rev past 3 7-max speed goes up to 70mph 8-drops the rev and speed when going uphill 9-sometimes on a flat road it drops the speed to 20mph and rev won’t past 2 10-recently got it services and changed all the filters including fuel filter . 11-i have got a cheap OBD scanner and saw a fuel pressure on live data it shows 22000 and it’s still won’t go up and down when rev . 12-when sudden floor the gas paddle it will drop the speed rev won’t go up it feels like fuel not coming or exhaust is blocked ,fuel or exhaust system feel squeezed .but if rev it slowly /gradually then it picks up speed until I floor the peddle but when release the paddle half way up then it feels bit of ease . 13-sorry for the very long message but I wanted some help desperately and wanted to describe as much as possible .been to land hover specialist and few other garages but no joy ,some say it’s an electric issue and some say it’s a high school reassure fuel pump and some say it’s a turbo or pcm issue but no 1 is able to figure it out exactly .. ( I have a short video uploaded as well on KZbin ) any help would be appreciated.👍

[@herkko61]

Do you have a digital or analog MAF?

[@glenbrown9379]

Thanks for an extremely thoughtful & through explanation. I was having trouble understanding the hertz output but I think I do now. I will watch this video many more times.

[@SchrodingersBox]

Good for you bro!!!! Yes most people (myself included) have to see material like this several times before it sinks in. Once it does- you'll never forget it.

[@flavianogimongala5320]

Thanks Matthew.

[@brunopecego5297]

hey Matt are you sure on GM signal and groud are not connected inside when off vehicle? i just saw Paul Danner on gm maf video saying that signal is grounded by a transistor inside the sensor and not by the computer. but now i dont know if when its off it stays connected to ground or open. maybe your sensor is bad because i just bought new one and mine there is continuity.

[@arthurfricchione8119]

Will also be purchasing the Autoingenuity scanner program.

[@deansergio5008]

thank you for your time and effort.learning alot

[@oluwoleemmanuel7611]

Please I wish to join u in ur garage to learn more on diagnosis. Wanna know what it cost to get the engine analyzer. Thanks in advance .

[@waynesworld8930]

your awsome man thank you so much

[@rickythetechguy8124]

Love this video bro

[@SchrodingersBox]

I Appreciate that!!

[@rogersy7209]

Newer Digital Multitester was now have frequency measurement function and we can use it to measure frequency output of MAF Sensor.. example Fluke 17B+ Multitester.

[@bleachinuri]

the most valuable tool in any inventory, is always between your ears

[@SchrodingersBox]

bleachinuri Agreed! Wouldn't trade it for a Verus lol.

[@bleachinuri]

true but i still like my verus all most as much

[@Bigbuddyjoe]

Great video ! I have a 2000 ford ranger 2.5l with a lean code. The mass air flow sensor is reading 0.50 g/s with engine off and 2.21 g/s with engine on at idle. Is those normal readings ?

[@SchrodingersBox]

It depends. You have to combine it with other induction data. What are the fuel trims indicating?

[@Bigbuddyjoe]

@@SchrodingersBox short term with engine off is 36.7% and long term reads at 0.0%.

[@SchrodingersBox]

See what it is once LTFT stabilized and then calculate total trim and see where it goes.

[@daquilema2011]

always Great videos, Bro you are a master !

[@schrodingersboxquantummeka2008]

+daquilema2011 Thank my friend. I am hardly a master though- I am still learning. In fact since making this channel I realize I will never learn even 10% of this stuff lol

[@1984juant]

+Schrodinger's Box Quantum Mekanix where do you read this material mat???

[@SchrodingersBox]

+tecnico Almost always the source for my information is from factory service manuals.

[@1984juant]

+Schrodingers Box factory service manuals. i have the famous Haness and alldatadiy manuals but they dont seem to cover the information as deep as i would like. thanks

[@hbenred1384]

really good teaching. thank you so much

[@DJDevon3]

5:33 and also hydrocarbon. lol yeah we know what that look was about. fond memories.

[@SchrodingersBox]

***** LOL- there's a couple of hidden easter eggs for the long time subbies in this series lol. Wait til you see part 2 --- you will freak!!!!

[@wysetech2000]

Just for a little added info, some Fords incorporate the barometric sensor into the MAF sensor and have more wires connected..

[@SchrodingersBox]

wysetech2000 Oh hell- so that would be like an 8-pin connector then. Wow. Maybe the vantage pro pinout-cheatsheet not so bad after all lol