Wideband O2 sensors, Narrowband O2 sensors and Fuel trim.

In this video i diagnose a car with fault codes caused by a bad Wideband O2 sensor.
While we diagnose this fault let's talk about;
Wideband O2 sensors, Narrowband O2 sensors, fuel trims and their relation.

[@DevonBbrown]

Best automotive teacher I've ever seen.

[@theGADGETSplaylist]

This video should be mandatory in auto schools. Well done, Dan!

[@Diagnosedan]

logical canuck Thanks!👍🤪

[@flyingarts6765]

ALL Dan's videos should be in auto schools. You are the best Dan!

[@akdasal-manasseer1520]

Fully agreed

[@D3M3NT3Dstrang3r]

I had to diagnose a stalling problem on a 95 Stratus 3.5. Long story short fuel trim max high bank 1 and then max lean on bank 2. When reset it would run for a few minutes until the trims would do it again but sometimes swap sides. Long story short the engine had been swapped with 1 year newer and bank 1 & 2 were reversed in the harness on that year model. Computer would see bank 1 go lean and enrich bank 2, bank 2 seen rich and lean bank 1 some more. That was a fun one.

[@WHS-Auto]

They are in my classes. Willcox, AZ High School

[@triniscorp]

Hey Dan I know this video is a couple of years old but it just saved me over $2000 dollars. 2006 Acura TL 216,000 miles P0420 catalyst below threshold bank 1. But short term and long term fuel trimmed maxed out. Downstream sensors were reading lean condition.Sprayed carb cleaner to verify downstream o2 sensors were working. They were. Long story short coolant temp sensor was +40° off. Making the ECU think the car was hotter than it was and giving less fuel. Which the o2 sensors were reading and ecu trying to compensate with fuel trim. No 02 sensor replacement ($200 × 4) no catalytic converter replacement ($600 ×2). I do my own work (free). $30 coolant temp sensor fixed everything. Cant thank you enough. If you're ever in NYC I owe you a ton of beers.

[@dannykapito6667]

You are teaching the whole Earth Mr. Your teachings are better than those at the University

[@philh9238]

this dude is smart he knows how to explain things simple to understand!

[@Diagnosedan]

My wife thinks I'm dumb🤣🤣

[@kigors1]

@@Diagnosedan Great thanks to your wife, otherwise we never know if you would try to prove yourself opposite by explaining us thinks in such an excellent way. So, when she says so, let's think this is the way how she develops your talent.

[@ryanramlochan1504]

Are you familiar with nissan tiida latio

[@MrFryfish]

@@Diagnosedan all wifes are the same. Women, they hate each other, and they're partners/husbands (after a while..) because we share and admit the clever among us, while them/they're, nothing like that.. brotherhood of man. And I swear I am not misogin..

[@The_Redkween]

@@Diagnosedan 😂 I know how that goes!

[@Autofixpals]

Awesome video, So many great uses for brake cleaner lol... another way to verify O2 and A/F ratio sensor operation from the driver seat (on vehicles with vacum power brakes) is to pump the brake pedal rapidly for a few seconds, this will force the system lean and when you stop pumping the brake pedal the system will go rich for a little bit. All you have to do is monitor the sensors and see which one is not responding 😊

[@Diagnosedan]

👍👍😉

[@LAW-fv6ys]

Great tip!

[@trealwilliams1563]

And... another way to verify brake-clean💯

[@shakeelsss]

Except on our skin

[@jeffreyellis5343]

Now in my sixties and having left the auto technician career behind (25 years ago) for tool and die, I'm thinking of a return. Of course it'll be my own shop. Who would hire an old guy? With your ability to explain various systems you've brought back my mojo. I totally understand you. Thank you for these videos. You are an inspiration.

[@razobaghd1696]

We have a lifelong respect for a teacher like you. God bless you.

[@Diagnosedan]

Thank you👍

[@ricardobuciobustamante4261]

Me to grate respect

[@a.c.e.7568]

I am watching this video over and over again. Amazingly that other shop replaced a common part that would affect both banks (the MAF sensor) when the vehicle only had an issue with bank 1. Too many parts replacers out there in the industry without "diagnostic" skills. I see it as "keep on throwing parts at the vehicle till the problem goes away"...sorry, but not on my wallet. I love these videos!

[@Diagnosedan]

Thanks for the great comment!

[@PeaceBeTheJourney.]

I cannot think of another skilled trade where we are required to have such vast knowledge yet earn such poor pay.

[@joshuaspencer6246]

Within time constraints and owning/needing costly tooling/equipment as well.

[@bengkelbawahpokok6753]

Not to mention the safety risk and health effects. My shop refused to provide us with safety glasses, mask, ear plugs or knee pads. They provide a cheap safety shoe once a year so if you worn it out, they wont replace it for you. The gloves they gave are cheap cloth ones, not oil resistant nitrile. Used engine oil causes cancer

[@09fatbobmike]

Poor pay? My tuner charger me 1100 for 4 hours of dyno tuning. Y'all charge 80 to 120 per hour for labor. How's that poor pay? I was a mechanic for the army for 14 years. It's not hard labor. And tuning requires knowledge. But that's it.

[@bengkelbawahpokok6753]

@@09fatbobmike We probably get $11 - $25 per hour from that 80 - 100

[@09fatbobmike]

@@bengkelbawahpokok6753 WELL thats some shitty shit there. time to start your own business. 25 is good but anything under 16 is under paid.

[@richard1835]

I have a 2001 330i coming in Friday. While I was servicing the A/C system he was telling me about the problems he has been having with the vehicle. I scanned it and found numerous codes related to the O2 sensors on banks one and two as well as a Number one misfire. I also found a DME fault code. He told me numerous shops have replaced the O2 sensors MAF Sensor and it had a tune-up. He is bringing the vehicle back Friday for a more though diagnostic. I will have a plan of action in place to better diagnose his vehicle's issues. Thank you for a very informative video on the Wideband O2 sensors and fuel trims.

[@evangelistjaphethcj.7755]

You have been my great teacher,since i started following u up i have improved i lot in my career as auto electricians. I want to say a big thanks to u.

[@Diagnosedan]

That's a big honor, Thank you!

[@autodiagnosticogonzalez6192]

You are the better of the diagnostics, God bless you dude!!!

[@Diagnosedan]

Thanks! 😊

[@michaelangeloferrari4024]

Your videos explain everything very clearly. No one does it better.

[@Diagnosedan]

Michaelangelo Ferrari Thanks!😁

[@alext9067]

That's a James Bond song. Nobody Does It Better. Dan's new name is Bond, James Bond.

[@EngineMisfire]

If I had seen your video a while back, you would have saved me many hours of debugging time and research on this topic. Hats off to you sir.

[@TRG972]

Former dealer driveability technician here. Impressive explanation of narrow vs wideband and relationship with fuel trim. You have a new subscriber.

[@gregjones8501]

Thanks to your videos I learned to look at my data and it helped me to diagnose an 05 Infiniti with a long crank time and lean readings on both o2 sensors. No lean codes were stored and car ran perfect when it started.

[@Diagnosedan]

Gregory Jones Nice!💪

[@spaceboundmg]

Watching this video 4 years after it came out and im amazed. Dan, thank you for setting this up and explaining all of this simple and very easy to understand!!

[@Autofixpals]

That BMW uses a Valvtronic system. Basically it can control valve lift electronically which pretty much eliminates the need for a throttle plate and this is the reason there is no vacuum at the manifold because air flow is controlled by controlling valve lift instead of a throttle plate. This system is very similar to what Nissan Calls VVEL (vairable Valve Electronic Lift). It's pretty slick.

[@Diagnosedan]

Exactly!👍💪

[@traqnsavov822]

Мu BMW is a valvetronic is a nightmare for repair

[@Diagnosedan]

@@traqnsavov822 it's not to bad

[@traqnsavov822]

my is valvetronic TYPE 1 is not very good, you is TYPE2 is good :)

[@dalemeasurall2226]

Traqn was my first weekend at the lake at the beach and my friends at the park at my moms t you can not get gym and the people Savov

[@Saykes1994]

13:36 Because the engine has a valvatronic system, which replaces the operation of the throttle valve, and instead of it, the valves open at a certain height, and not the throttle valve. And the typical pressure in the intake manifold is close to 950 millibars normal atmospheric pressure is 1013 millibars. Typical vacuum in most naturally aspirated engines is 300...350 millibars.

[@jb_bmwrepairlyfe4704]

Keep making these videos keep chiseling our brains as technicians! So far you have not lost me because of the thorough explanations!

[@matepro2643]

Brilliant Dr, Dan. Actually, you are answering what would the audience ask u. Thanks again

[@Servando054]

I like watching people like Dan, intelligent ,funny love what he does. I like to help and teach people too, feels so good,, the more we learn the better we get. this world will be better

[@MetaphysicalChris]

Dude, you are awesome! helped me with Wide band O2 sensors. Clearer than anything else so far.

[@Diagnosedan]

Christopher Rumfield thanks for the nice comment buddy it's appreciated!

[@sambitar8448]

HI DAN; TOTALLY IMPRESSIVE DIAGNOSTICS. RIGHT TO THE POINT. YOU ARE A GREAT ASSESTS TO THE AUTOMOTIVE FIELD. THANK YOU

[@bficful]

Dan - you killed it ! So clear and concise. Grateful you took the time to post this. Really helped explain the P0172 I had on my Subaru Forester.

[@hftiller]

Diagnose Dan, you are the MAN!!! I ran across one of your videos the other day and I am such a fan now. You are exactly what the new generation needs as a common sense back to basics teacher. You are mandatory must watch for my younger crew. Keep doing what you do and we will keep subscribing, watching and spreading the word!!!

[@dominicdo]

Thanks for making it easier to remember Dan. I always like your videos you are a top notch trainer.

[@Diagnosedan]

Thanks!😊👍

[@randykozoris8096]

This is the best explanation of the o2 sensors I have seen. Dan you are a great teacher, keep up the fine work.

[@godfatheratlsu]

Great video, Dan. I'm a long-time self-taught garage mechanic working mostly on German cars, especially on BMW's. And I'm also learning even more by just watching this video. To answer your bonus question, I think there is still a slight vacuum after you remove the MAP sensor, or else, this Naturally Aspired combustion simply won't work. And the reason that even when you articulate an artificial leak in the intake manifold and still maintained a stoich condition is because of BMW's VALVETRONIC system in place. Under the VALVETRONIC system, the throttle body no longer plays a key role in intake air control. In fact, you can have the throttle body fully open the whole time and it won't make a difference as long as the O2 sensors are properly working and nothing being wrong with the fuel supply. Actual fine control of the air is done by the intake cams which is fully modulated by the VALVETRONIC system.

[@jdmtechllc6589]

Hey Pete spot on man! Also, our after cat 02 sensors do influence mixture on BMW’s by providing a reference point.

[@alilakis2527]

Correct Sir

[@NOne-yt1tj]

Every time I have a fieling issue with my bmw i come back to this video, which helps me interpret data from my car. Many thanks for this video

[@kyhomegarage3430]

Excellent case study my friend. Thank you for your time to bring these video to us. Cheeers

[@Diagnosedan]

Thanks! and thank you for doing the same👍

[@quincym526]

Great job explaining this in simple terms! Best teacher so far! Im very gratefull for your very helpfull videos!

[@ferenctulics9688]

A another easy to understand lesson. Thank you for all your sacrifices you made in order to offer these videos to us! I Can't stop watching your videos, they're so contagious! :-)

[@Diagnosedan]

Thanks for the great comment 👍👍👍

[@ksauto1]

I agree with Ferenc-thanks again "Dan the. man"!!

[@brunocorrea6010]

Awesome! I always wonder what was that short and long term fuel trim on scanners and never found neither the classes I took told the answer. Thank you for this video, strictly to the point and calm talking, very well teached!

[@ljsambell2215]

Excellent coverage - thank you very much - and I especially like how you determined to add some fuel ( brake cleaner) and see if and how the narrow band sensor downstream responded in order to validate the upstream unit.

[@PaulAstefanei]

Just discovered your awesome channel. I guess the answer to your question is the fact that there is no throttle valve on this particular model. That role is taken by the Valvetronic system.

[@billsullivan8812]

Outstanding Dan! even mechanics can learn from this, Extremely well done.

[@Diagnosedan]

Thanks Bill.

[@picoboo5048]

Great info, the illustrations really help to understand what is happening

[@Diagnosedan]

Pico Boo, Thanx😀!

[@fuzzs8970]

You see i am not having any such problem on my car, i am not even a mechanic, however i really enjoy your shows. They are informative and nicely presented. You are way better than lots of teachers and some tv shows.

[@nemeciomanuel1022]

You are the real thing. I'm new watching your videos and Im really happy I found your KZbin channel. Thank you for sharing your knowledge.

[@piotrk5308]

THANK YOU DAN FOR YOUR TIME .... YOU ARE AWSOME TEACHER

[@Diagnosedan]

Piotr K Thanks for the nice comment buddy it's appreciated!😉

[@jasoneyes01]

What a great lesson Dan. My understanding of O2 sensors was basic till I watched your presentation. This topic is deep. I was glad you presented it in a slowed manner. I was actually haveing mental gymnastics calculating what you were presenting. Never knew widebands were current sensors. Just replaced the downstream sensors in my 180000 mile N62TU. Car runs so much smoother. I think the downstream sensors play a role in fuel trim, not just cat effieciency monitors which was the code I got on bank 1 and 2. I have no clue on the algrithms BMW uses in the DME.

[@miguelrivero7067]

You are a great teacher Dan!👍🏼 thank you! If I’m not mistaken that BMW also have an absolute pressure sensor in the intake manifold, which will not sense an intake air leak.

[@Shelby-ug5cl]

Hey Dan Thanks for posting these videos your are a great teacher. I have been watching your videos for a little while now and I have learnt alot. I have been applying your technical advice in the field and using scopes more often than I use too. I try keep it simple and not be a part changer thanks to you and several out their I am becoming better and enjoying diagnosis more. I will try to to pass the torch. Of knowledge to our fellow technicians out there as you are. Thanks again. For the answer to question for no vacuum on bmw its due to the valve tronics it act like the throttle and the actual throttle stays open all the time which does not allow negative pressure (vacuum). Bmw actually installed a vacuum pump driven by engine camshaft. I think when system goes on fail safe throttle may operate like a normal throttle open and closing not sure correct me if I am wrong. Anyway keep up these great videos and I will keep watching. Your awesome

[@salahkebi05]

You have that ability to explain complicated things in an easy way...great job danny, btw i've scrolled down almost all the comments and haven't found the ansewer...

[@oda0111]

Very good video Dan! Always a pleasure watching them.

[@Diagnosedan]

Alin Marinescu Thank you!😉

[@steveguest8028]

Dan I’m impressed,best easiest to understand description of narrow and wide band sensors I’ve seen so far....Many Thanks 👍🏻

[@Diagnosedan]

Your welcome Steve👍

[@600322]

The problem is that Dan is very gifted and only works with expensive cars.Can I learn from him without any extra money? Yes!

[@jimmydaniel4203]

Watch your videos a lot. You are the best! As a long time shop owner I often use your instruction to help my techs to never forget the basics! Your breakdowns are awesome! Thanks for all you do for our industry!!!

[@Diagnosedan]

Thank you very much Jimmy👍👍

[@weecha7063]

Learn so much from you in the span of 6 mins and learn that my upstream 02s is needing replacing thank you!

[@georgema620]

You are the King of diagnoses 🙌, I learn so much from you😎

[@digitalmonkey3286]

Very informative and well done video! Thank you, Dan!

[@richardlewis7471]

Great video! You put it all together in a very understandable way. Thank you.

[@a.c.e.7568]

Well I didn't know what Valvetronic is since I do not own a BMW car (my last one was a 1995 E36) and my BMW motorcycles do not use that system either. My guess was a MAP sensor only needs a tiny hole to measure pressure (since it is static and not dynamic) and that tiny hole would not allow enough air to enter the engine. But this video is excellent to understand about Fuel Trim (I had no clue about trim)! My friends Porsche 993 is running ultra rich after having the engine out for seals, o-rings and a new dual mass flywheel and clutch. Plus we did the 964 mod to the 993 cams to pin the timing gears to the camshaft (the original 993 gear is a butt fit to the camshaft using a bolt...in my books a no-no). Anyway, I think we will have to do an ECU Drive Cycle / Readiness. Thumbs Up Dan!

[@Diagnosedan]

Thanks for the great comment buddy it's appreciated

[@vincentwoodward1752]

thank you for the video I've had a hard time finding good explanations of wideband, narrowband, and the relation between the two with new systems that use both oxygen sensors for fuel trims. Next is Biased Voltage sensors.

[@markoguberinic]

You are the best diagnostician and lecturer I have seen. thank you🫡🫡🫡👏🏻👏🏻👏🏻👏🏻

[@TommyOhmalley]

Honestly great work Dan. Informative and concise.

[@cindyeva7454]

Thanks for the great videos,sharing them with the younger techs on my team to sharpen their skills

[@Diagnosedan]

That's great! Thanks for sharing!

[@IamReadyToRock]

my friend, you are right, in engines with valvetronic there is no vacuum in the intake manifold, one way to create vacuum would be to disconnect the valvetronic motor to force the system to work with the throttle body in this way, the throttle valve now will be closed, and there will be vacuum in the intake manifold. I read you Dan 👍🏽 from Peru

[@nyronm941]

Well put Dan, very easy to follow your explanations. Thanks Dan

[@Chris-wp3ew]

Very informative... After replacing my injectors, I started noticing backfiring.. I never thought a lean condition could cause that.... Your video has inspired me to send the injectors off to be tested and after I replace them, I'll check my O2 sensors. Thank you

[@jamesbruno5896]

Great detailed explanation Dan! Thanks for taking the time to film this! 👍

[@rogerpearson9081]

I have a Commodore with a Buick derived engine. { Australia) I will stick with its simplicity compared to these Euro engines with multiple O2 sensors and variable valve timing. So far 280,000 kilometres and still on original injectors and sensors. I can do a lot of the work myself unlike these complex cars which need some expensive equipment to diagnose. Still very fascinating learning how all this new fangled stuff works. Really appreciate your time and dedication producing this training grade series.

[@matthewash8349]

This helped me understand why my Narrowband replacement o2 sensors weren't working... my car was designed for Wideband sensors! Thanks!

[@rudolfhuijs4526]

Best short/long term fuel trims explanation video. It had to be a Dutch guy. Mooie!

[@HelgiThorisson]

This video is so good that I watch it over and over again.

[@mistikajimenez6348]

Good information about the O2 sensors, thank you for sharing your knowledge.

[@Diagnosedan]

Your welcome!

[@frvanderburg]

Well done! Even a non-carmechanic like me totaly understood your story. Thnx

[@harindersran4838]

Fuel trim was always a problem for me to understand before i watch this video. Thankyou v much

[@billrimmer5596]

What a wonderful tool to have in our database. Thank u Diagnose Dan!!

[@lawsonthursfield6950]

Awesome video as always Dan , was at work today working on vehicle with wide band sensor , it’s never too late to Learn more 👍

[@JasonSpiffy]

Very clear explanation and great video! Where does one learn this level of knowledge. You inspire me to want to learn.

[@CHIBA280CRV]

Thank you Dan , your videos are very helpful and very informative. I appreciate your wisdom..

[@carltaylor7489]

Dan you are the man I love watching your videos and I wasn't 100% sure on 02 sensors narrow and wide band you have just explained that and it all make sense now and fallen into place thank you

[@valeryizotov4987]

I watch your video as a good series. Not every educational institution explains so well. As they say there are no bad students, there is a bad teacher.

[@augustinelandicini9813]

Awesome video thank you Dan the man . System bmw came out with I believe it’s called vanos which requires no throttle plate so that engine rpm is changed through variable valve lift

[@fishin4salmon]

Awesome videos Dan. I have really learned a lot and they keep me wanting to watch more just for fun. Thanks.

[@tomatal1]

Nice!! Truly enjoy your videos.. very informative and clear. Awesome job Dan!! You definitely a Master at what you do.. I salute you sir 👍🏼 👍🏼

[@HamiltonSRink]

Thanks Dan! Clear explanation makes it easy to learn!

[@fredsalter1915]

Superb explanation of fuel trims! Very helpful for me!

[@Masso1973]

Thank you, Dan, cleared up a misconception in my head about wide band, now I’ve got conception :p

[@alexklaus8438]

Just discovered you and glad I did you're a great teacher!!!

[@Diagnosedan]

Great to have you here!

[@TheJm1234321]

Thankyou. Your explanation is very clear compare to my instructor

[@osmargds]

Thank You so much for your explanation! You explain so well! Love from Brazil!!!

[@nowshadalikhan7522]

Important information is simple words, great video. Thanks for uploading

[@rrmech11]

I'm glad I came across your channel. Probably cause the variable valve lift is your answer

[@Diagnosedan]

Richard Gill, did you watch all my video's at once🤣🤣🤣🤣. Thanks buddy glad you like my channel. And Welcome!😁

[@ednewell1847]

Great content in this video! I am surprised that BMW does not have a back up fuel strategy for circumstances like this, a lot of the Asian vehicles use downstream fuel trims when they have a upstream wideband

[@Diagnosedan]

Eddie, Thank's for your feedback!😎

[@1718blazer]

I’m late to the party as I just discovered your channel. Excellent instruction and trouble shooting. Keep it up. Looking forward to more videos.

[@buzzbuzzard9469]

Thank you Dan....Great channel and great kids...I Will look into the VVT system

[@Diagnosedan]

Thanks!

[@williamguy1932]

You are an excellent teacher. So clear.

[@user-up7ol2ri7p]

It is very simple and easy to understand.Thank you!

[@rachelcurd4714]

This is a very good video presented in a methodical manner. To answer your final question about why that engine had pressure in the manifold it is a valvetronic engine. As a former BMW trained technician the initial give away is the bulge in the valve cover. Not sure if you have done a video on that system as this is the first off you videos I have seen Regards Ian

[@shinola228]

I had to watch it a couple of times but finally got it. Excellent video . Thank you for making it.

[@johnavila7942]

Just keep watching over and over till u get it . That’s what I did and now I understand thanks dan 👍🏻

[@LAW-fv6ys]

Smashing video once again Dan. This test can also be used to diagnose a fuel injector fault! Running lean and both o2 sensor working ok but engine runs better adding brake cleaner means injector fault. Watching the smooth running values on these engines also helps understand the cylinders which aren't performing well, positive numbers indicate less mechanical output of the cylinder. Dont forget on most newer BMW and mini deleting codes doesn't reset the fuel trim adaptations or injector learnt values etc , so you may change faulty parts and car still runs bad with learnt values which are incorrect. Injectors for all gdi engines must be coded.

[@abdul-kabiralegbe5660]

Always wondered what the Injector Coding function on scan tools did. Thanks.

[@PasiviN]

I have been driving myself insane troubleshooting a failed smog on my 98 boxster. Fuel trim negative, indicating rich. But downstream shows 0.1 or 0.05, lean. This video explained clearly that it's likely an upstream. Untill now I have been watching voltage instead. Thanks for the help.

[@Bgroup80]

I wish there is option for million likes i would have given all like for this explanation❤❤❤❤🎉🎉🎉 brilliant practical explanation i have seen.. thank you so much..

[@janveit2226]

Very good video. Short, clear and made simple

[@Cees1984]

Goed kanaal Dan! Top diagnose technicus aan 't werk, bedankt voor het delen

[@Diagnosedan]

Graag gedaan, bedankt voor het kijken!👍👍