How to Test a Mass Air Flow MAF Sensor - Without a Wiring Diagram

[@thomastucker8167]

Thank you for your videos. You have helped me do timing belt,water pump,head gasket and test the MAF sensor on my 2004 vw Passat wagon. 1.8t.

[@egorkay]

You just summed up vw ownership in one comment lol

[@markalesio8019]

Fantastic explanation. Easy to understand. No unnecessary prattle. I'm inspired to work on my car.

[@alexmorgan3819]

thank you for sharing your reliable information with us , I did not know how to check MAF sensor , now I know thanks to you.

[@merlin1346]

Simplest and most accurate explanation so far.

[@tomlatimer5001]

Exceptional video! Explained well without all the extra dribble 99 out of a 100 how to videos have. Maybe you should do a how to video on how to make a how to video, he he.

[@davekauffman8727]

Thanks for a video that didn't have a shop with expensive equipment and tools.

[@omareid8166]

Thanks for this awesome video continue in these episodes we thank you from the bottom of our hearts

[@robertbusack2100]

Wow!!! thanks for all the tips/info... Couldnt have done it without You!! Many thanks,bob

[@chrishoesing5455]

Thanks for making a video, but you might have wanted to point out that this only works with MAF sensors that vary voltage on their output, where most will vary the frequency. The latter you would need an oscilloscope to get a useable reading. So, it would be difficult to know which type you have which would negate the useability of this testing method. My particular MAF sensor varied frequency, and so it just had a constant 2.8v that didn't vary with rpm. The new one was an non-varying 3.1v. Thankfully the new one did fix my problem, but the testing method didn't work in my case.

[@MajDuty]

Mic drop

[@misterbulger]

great video. I am confident I can get this sorted out now. I think the replacement unit they sent me is bad too. Sigh.

[@CycloneCyd]

Check the wiring before taking it back though! If it is the wiring you'll be on a wild goose chase with replacement MAFs

[@Nutzername1273]

Very nice step by step for beginners with the multimeter like me! Thank you very much!:)

[@marvinwatts8392]

Nice and easy steps to identify the MAF wiring

[@backroadhustler8687]

Nice, excellent demonstration thanks for the video

[@bart776r4]

Good info, good details. Thanks for posting.

[@yousefagila234]

Thank you for these videos, clear and very good explanation.

[@Cacciaallalepre]

Thank you bro! U helped me with your detailed exp. 💪💪💪

[@viplegaleducation1292]

Simple and straight forward. Love the content

[@ahsansha8678]

Best explanation 👌

[@DougieD61]

Very helpful. The holes in my wiring harness are too tight to accommodate a nail, and the paper clip ends are too blunt to get in next to the wire. I used a couple sewing pins, which are kind of T-shaped. They're sturdy, yet you can bend them away from each other once the pin end is inserted. I imagine pulled-open safety pins would work, too, or even straight pins. I tried using twist-tie wire, but it was too weak to allow it to be pushed in far enough.

[@duanejohnson4383]

safety pin

[@BellaGartenLLC]

Dougie D You can buy thinner and sharp test leads or just use a scanner

[@jgeorges3061]

good info as always thanks for sharing.so the idea is to put the voltmeter on the re ferns and censer ground wire to find the movement of tps as voltage changes.

[@victornaja-paz5241]

very well explained. thank you!

[@aileenaie]

i really enjoyed watching your videos..i have learned a lot..

[@sebulva]

thank you for taking the time to make these videos

[@OilBaron100]

Really useful! Thanks for posting

[@danrozelle6737]

This was a good video just to understand the basic system and how it works. I am having problem the MAS sensor sending a signal that is two high and the computer switches over to a automatic mode to let the car run but not entirely correctly. The light comes on. Anyway I was wondering that if I am having compatibility issue with aftermarket versus factory bosch sensors and the volvo computer doesn't read the china sensor outputs correctly. I have tried three. Of course they make the factory sensor so freaking expensive. It is almost unaffordable to drive a Volvo and get it repaired. They have everything so controlled and tied to the factory. Anyway. This gave me a better understanding of what is going on and I think I am going to play around with a potentiometer and change the signal to the computer to see if I can trick it into leaving the light off and not throwing a code. Anyway. Its fun trying...

[@nicholasphilip-neri2431]

I enjoyed watching your videos!

[@mikeburgan6350]

Great video and explanation!

[@majordog85]

Great explanation carnal, muchas gracias. New subscriber here!

[@ksg7821]

Well explained. Thank you.

[@Bio3rd3]

Thank you for the tips it was very useful, god bless

[@everardocamacho5063]

very good video, as all you have, keep up the good work, cheers from Ontario ca,

[@MrPaulo1147]

Hello, there. Great video andn really well explained. I have a w203 c180K 2004, and since last year when starting the car, it started taking longer than usual and the car started to have misfires when in lowgear and it seemed it like it would die... Took it to a mechanic and he disconnected the maf sensor, and the problem stopped "chocking" but the start still takes a long time when i turn the key... I bought a new MAF sensor to replace it, and lo and behold, the problem persisted.... So I so some of your videos of how to test the maf. And guess what i found. On the first step, when looking for the 12v pin (it has 04 pins), i tuned the key on, grounded the multimeter, and set do 20dcv... and guess what i found... 12v on 03 pins and 0v on one... Now, my questions is.... What might be the problem? I live in Brazil, and where i live there aren´t many people that understand how german car works. Got any tips for me? Thanks and looking forward to a reply.

[@jamiemccort8388]

Thanks mate 👍🏻 very helpful 👌🏻

[@freshstart3555]

Good lighting on the Video. Okay Harbor Freight multi meter. I have that one. Good stuff.

[@CycloneCyd]

Which one? There are two shown at the beginning.I'd go for the bigger of the two. It's very similar to the Rapitest DM25 I use. Reason I have that is because it can read mVac. Without mVac you cannot test ABS sensors or crank/cam sensors

[@jesssmart7545]

What was the wires that the paper clips was connected to? Voltage and ground?

[@globaltefl]

Loved your video--easy to follow, well done. I have a 2007 Audi a4 2.0. The Air Flow Sensor has only three wires. Which one would be missing?

[@ezwa9979]

good video, my maf’s got 8 pins so, so much for that process of deduction to figure out wats the sensor ground. speaking there-of, what’s the difference between constant ground & sensor ground?🤔

[@lawsonstallings1955]

Great job. Well done video.

[@MrAustrianoak]

I know it's an old video, but you have maf signal wire and the other is the reference voltage and not the signal ground if I am not mistaken.

[@silverback1540]

Very good explanation, just what i needed. Thanks

[@michaelharris8354]

Your videos are great and well explained. Thank you

[@frankvasquez1387]

U R a Bad Bato my friend! Excelente video and clear understandable explanation and steps! Keep up the excellent videos and thanks a million! Good Brain CACA !

[@gordonbarclay6106]

Fab, however would you not get an engine warning light come on when you disconnected the MAF sensor then turned the ignition on ..

[@adanarceo4636]

Hey brother good job, but what about when you have 5 wires instead of 4,what the fifth wire will be for? Thanks again for sharing your knowledge 👍👍👍

[@cadwellma]

Intake air temp sensor built into MAF sensor

[@raestephen242]

Mine have 7 wires bro. Mitsubishi space wagon.

[@philstat100]

Thank You for the great video and information. That engine compartment looks exactly like mine, 2003 f150 xl 4.2l. If my MAF sensor is bad, How do I remove it from the breather tube? Again Thank You

[@michaeltorres9575]

GREAT VIDEO MAN, THX A LOT KEEP UP THE GOOD WORK

[@warrenpowell9233]

I understood it,I liked it

[@justinarthur3601]

Can you test the MAS if your truck won't stay running. And can a bad MAS cause it not to start or to die within a few seconds or cause surging when idling

[@jimringo2569]

What if the spark is checked good and the fuel rail pressure is good but will not start when cranked? Will any test on the MAF show any information if the car will not start? Thank you for your efforts, been watching many years.

[@israeltravieso3926]

As a newbie , i need to ask do you keep ignition on for resistance test?

[@mrakjunior]

Your videos are simple to understand and practical as well thanks a lot.

[@zafarshaikh6209]

Awesome dude I have a good knowledge

[@monirobaid5809]

Hi, I am in the process of repairing the mass air flow sensor connector wiring. As a result of the mice messing around, I cut the wires off the connector side, leaving approximately two inches for each wire attached to the connector. I thought each wire was a different color, but I was surprised to find two wires of the same color. I drive a 2006 Infiniti M35 with a maf sensor that has 5 wires in this order from left to right: red, black/white, white, yellow/green, black/white, so I connected the 3 different colored wires and was left confused about the two Of the same color. I tried connecting this to this and vice versa and I did not feel any difference. I also tested them with a multimeter and they both gave the same measurement. So if you have any idea or suggestion that can help, will be appreciated

[@RonComstock]

on my explorer 92, i get code 157,158, low and high voltage codes, check engine light on , I get .01 . check engine light off i get .53 . it is an intermittent thing. checked wires for shorts, none, runs crappy at idle and when driving it will stumble slightly right before check engine light comes back on. I can also unplug maf and plug back in check engine light goes off. yes I cleaned contacts just to make sure it wasn't a short at plug. my question is, would this indicate a faulty maf or one thats getting ready to completely fail?

[@jtaylor4027]

When backprobing the signal wires, did you connect the plug back to the MAF sensor?

[@memphesss]

So useful but from where you know how much is a value for each of sensors.

[@uldaricocuba4779]

request, if you can show how to test electronic power steering wiring without scanner, thanx

[@miketransporter5638]

What does is mean if the voltage doesn't go up while revving engine. Or very low reading on idle

[@BellaGartenLLC]

Make sure you don’t ground out the + wire. Also keep in mind you can create false codes by disconnecting sensors with the key ON. Don’t throw parts at ghost codes you created yourself (or others created). Hence the importance of erasing codes and and seeing if they still persist. That’s why scanners with LIVE DATA can have advantages. Also you don’t want to trigger a “Limp Home” mode with decreased performance from triggering “False Codes.”

[@MrJAa85]

Question; in this case, would it really matter which of the ground wires you used in the testing? They are both constant grounds here, are they not? Or battery negative for that matter? When testing the voltage from the signal wire I mean :)

[@Michael_Lorenson]

Excellent, thanks.

[@16mmDJ]

Thank you so much!!

[@ryanramlochan1504]

You have any videos with a 5 pin maf sensor

[@alexionsigubudu560]

Just a silly question, can an MAF sensor stall the car? I have a Benz C220 diesel, it starts and dies, any suggestions please?

[@luisaliceaortiz7791]

Thank you stay blessed

[@amirouw]

Does this really help diagnosing a bad map sensor? What if map sensor had a bad calibration?

[@Volvoamazon62]

Hi, just saw a video where someone just unplugged the connector and when the engine stops, it's not broken. Is it that simple?? Why do you need to measure?

[@jtaylor4027]

I read that and tried it on my 2001 bmw 325i. While connected it stalls and shuts off but disconnected it runs. Buying one today but it has been running unplugged for 3 months.

[@macknumber9]

@@jtaylor4027 how is it running now?

[@c-van-sycoz835]

Best info... Ever

[@brettlynch9427]

My 2000 ranger 4.0 ohv reads about 1.1-1.0 on start up and settles down to about .8 is that normal or is that too low?

[@drakesshion3174]

Question @ 2:18 turing on the the ignition will send power to the sensor via 2 wires?

[@jamesrooney7689]

where does the harness end where does it go to thank you

[@nicholasphilip-neri2431]

I am trying to locate the r camshaft position sensors on 2011 Range Rover sports?

[@TheUltimate65]

Can the airmassesrnsor work like bad of winter in cold weather the engine works rich mixture from cold start and stop ,after short time , when i start agin,running the engine nornaly ,of high rom,befire the rpm slow down and repite the rich mixture , the car its a 01 maxima,

[@120115135]

greet job amigo

[@offbeatmedia-farshad]

Hi, and thank you for the information. Question. My check engine light is on. The code reader shows P0102 which is the MAFS voltage low. There is no vacuum leak. Does this mean that my MAFS is bad because if I test the MAFS installed as you showed we already know that it is going to be low based on the code.

[@arnelangeles4718]

silly question, what if you test ohm resistance probe to constant voltage supply any damage to wiring harness?

[@pantelislolos9455]

so which wires did you exactly back probed when you tested them?

[@gweedomurray9923]

He connected the two sensor wires and not the hot 12v nor the ground.

[@Really658]

​@@gweedomurray9923 thanks. Appreciate it.

[@gweedomurray9923]

@@Really658 ~ :-)

[@Marginal391]

Thank you. Very helpful indeed :-)

[@dayntubee]

Dude! Whenever you measure the resistance of the ecu harness side, always disconnect the battery first!

[@JuanHernandez-ov8wv]

Actually,as long as u use a digital multimeter n not a 12 v test light u should be ok.so in a sense he is doing things t right way

[@RossWilliamsDC]

My multimeter is hooked up as described but my engine will not idle (it dies) unless I disconnect the TPS. Is this test accurate with the TPS disconnected? I'm getting around 5v with the TPS disconnected at cold idle. The exhaust is horrible I assume from a ton of unburnt gas. This vehicle (1990 Toy 4x4 pickup 3VZE Calif) has 7 pins at the MAS connector (3 hot 5v, 5v &12v, 2 Ground, a lead to the ECU and a THA) because the MAS has 3 functions. 1. MAS (Air Flow) 2. Fuel pump shut off if the engine dies for safety & 3. Air Temp in MAS. Isn't KZbin wonderful? It almost sounds like I know what I'm talking about. Not!

[@intizami]

I have nissan murano 2008 and fuel consumption is too high....I change plugs,clean the fuel injector and air filter change ,but no benefits at all. 25ltr _ 100km I need advice, what is the problem in the vehicle?

[@blinkskaterkc]

Simple and easy thanks.

[@myRatchets]

blinkskaterkc anytime, thanks for your comment. cheers

[@erniequibod9363]

Sir you have example of how to test the electronic egr

[@LayZeeDawg]

In 50 years our kids and grandkids will look back on these videos and wonder how we paid only 5.00 for a dvom that costs them 200.00

[@matutenoel4833]

good video amigo exselente. diagnostic

[@ra.dawkins1441]

Bro your so flipping smart. How???

[@victormiesner7804]

Thanks again

[@silvermcc2768]

i have a 97 gmc pickup, 5.7 had the code for MAF low voltage come up. seems to run alright. when i did the test on the sensor i get my 12 volts, good ground, at idle i get 4.48 volts, but when i accelerate the volts go down instead of up, they go down smoothly as the the RPMs go up , any reason? any suggestions??

[@hellhellya1]

silvermcc Hey bro did u ever figure this out? I have the same truck. Only mine runs bad with new sensor connected.

[@rinorgucati5128]

hi i changed the maf on my car and i have the code p0102 that wont go away any idea please ? thanks

[@roadstar499]

Okay so the last test when you increase and decrease throttle as well as see volatage go up then down is testing the Maf sensor or wiring going to Maf sensor? so if this test voltage reads wrong, how do you fix? You don't say anything on repairing... thax

[@CycloneCyd]

Yeah I noticed that too. Unfortunately if your MAF is faulty (try cleaning first), there is only one remedy and that's replacement. But yeah, he should have covered that I'd agree.

[@andriisliusar4334]

Hey, I followed step by step on old GM car(1994 Buick Century 1994). My MAF has 3 wires. Signal wire has constant output since i turned ignition on 2.4-2.6V(Doesn't meter car is idling or running on completely open throttle.) And car hesitate while idling especially when It's cold. After car warms up it gets a little bit better and hesitation almost disappears. I purchased new MAF from 1aauto - nothing changed(the same output = 2.4-2.6v). ANY IDEAS? And thank you for videos(unless with TPS diagnostic helped a lot for me!)

[@BenChung78]

Two possibilities. The less likely possibility is that 1) Your PCM ECU computer circuit might be shorted on the maf sensor internal computer circuitry which would mean even a brand new perfect maf sensor will not fix the problem...you would have to diagnose the ECU...scannerdanner on youtube has a good vid on how to do that. The more likely possibility is 2) You may not be using the correct red connection plug on the multimeter for your positive red lead connector to the multimeter...for maf sensors and depending upon the type of multimeter you have the V(ohm)mA port, not the mA port should be used to read the voltage readings. This difference will make a big difference in reading capacity as sensitivity to changes in 1-3 volts are difficult to pick up when your red connector lead is on the mA( designed to be used for 500+ volts). I would retest it making certain the red lead is on the lower setting of v(ohm)mA and not on the higher voltage setting. Let me know if it worked if you try it.

[@RC-Heli835]

Thanks man! I just checked the one on my 2000 Ford Windstar. Hot wire read 12.66V, both grounds registered 6.41V. Checking the signal wire, the voltage stayed around 6.94V no matter where the throttle was. I guess I have a bad MAF sensor? Or should I do more test?

[@myRatchets]

ILTSYC Not sure what you mean by both grounds registering 6.41 Volts? Follow the instructions in the video exactly, and step by step and you will know if the MAF is faulty.

[@RC-Heli835]

RatchetsAnd Wrenches I found the problem with my MAF sensor. After replacing head gaskets and putting everything back together, I had the windshield power supply plugged into the MAF sensor. Those two plugs are interchangeable . Its running great! No more surging at low RPM's and hard shifting. Thanks! One thing that made mine a tad more confusing was that it had six wires because the IAT is integrated into the MAF sensor.

[@eduardosolano837]

+Transguy Dumb af 😂😂

[@CycloneCyd]

Jeez - poor design!! Well done.

[@knightrida6829]

Big help

[@carlosarzu1210]

I have a question, I have a 2001 tundra and it stalls in drive & reverse

[@blass5506]

What happens if when accelerates the throttle the rpm increase sometimes hut others stay in 0

[@anujshukla2620]

Nice posting sir

[@1PoisonZone1]

in my opel astra h 1.3 cdti const is about 5v (MAF and MAP sensors) is that normal ?? my car cant use all power ://

[@zizozazo4638]

Yep, it is. In Your senor is a frequency regulation, voltaga stays constant.

[@khizerhusain5237]

Sir how to trace another two wire of map sensor

[@icarusi]

I may try this with some wire running back to the car interior so I can get MAF readings with the car in motion.

[@CycloneCyd]

Great idea, that would work well, but I'd seriously suggest you get someone else to drive while you watch the meter.ORUse one of these amzn.to/2m439QG and Torque Pro on your phone. Use the graphing function if you can't find an assistant to drive for you.

[@das250250]

Wouldn't it be better to examine the ground before you send live 12v to the harness to avoid meter damage

[@martinflint8226]

Hi at what point did he send 12v ?

[@mymechanicfriend6017]

Right on!