MAF and Wideband O2 Sensor Testing for a P0172 [Rich Condition]

The car being tested is a 2007 Suzuki SX4 but the methods shown apply to all cars! It is very difficult sometimes to identify proper operation of a wideband O2 sensor and also the calibration of the MAF sensor. In this video we cover both of these tests very thoroughly and are able to fix the car.
00:00 - customer complaint, repair history (rich condition P0172)
02:13 - upstream and downstream oxygen sensor testing
09:00 - fuel trim analysis
09:55 - common causes of rich conditions
10:15 - MAF sensor testing begins
16:30 - MAF sensor inspection and cleaning
20:00 - adding fuel to confirm wideband function
22:20 - Stink Bug Video • Nissan Pickup, Low Pow...
25:40 - lab scope tests of the MAF sensor
30:10 - day 2, used MAF sensor comparison
35:15 - why the "unplug it test" can get you in trouble • Why the MAF "unplug it...
36:50 - SD Premium Skewed MAF sensor case study Part 1 tinyurl.com/3ccpz2fb Part 2 tinyurl.com/32ubrjfd
37:10 - counter fuel trim numbers (is it fixed?)
39:30 - Understanding Short Term and Long Term Fuel Trim (a SD Premium video) • Understanding Short Te...
42:06 - scan data MAF and Calculated Load numbers after repair
43:10 - How to identify and clean a dirty MAF sensor (Subaru) • How to identify and cl...
46:55 - lab scope tests on the used MAF
ScannerDanner Tools:
www.scannerdanner.com/tools.html
www.amazon.com/shop/scannerda...
For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
Want even more diagnostic training? Whether you are a DIY trying to fix your own car, someone looking to become an auto technician, or a current auto technician that wants to get more into diagnostics, subscribe to ScannerDanner Premium www.scannerdanner.com/join-sc... There is a 14 day free trial.
On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!
Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC.

[@ScannerDanner]

Don't forget to check the description for time stamps and links to the other videos mentioned. Thank you everyone and Merry Christmas!

[@lawsonthursfield6950]

Merry Christmas to you and yours brother

[@janico76]

Merry Christmas to the Danner family.

[@dimisrambodimisrambo7285]

MERY CHRISTMAS MY FRIEND

[@arctican7483]

Merry Christmas and a Happy New Year!

[@horacemalone7964]

Www

[@justinballard7242]

4:57 you can rapidly stab the brake pedal to force a lean condition also. Eric o from sma taught me that trick

[@coycarlson4979]

Love living in the day and times of our internet technology especially being able to watch you teach me how to PROPERLY troubleshoot and repair vehicles - if I learn half of what you KNOW and Teach - I will be a good tech 🙂 - That being said , you are inspiring and I want to be just as good as you - not just half as good 😏 . The reality of it is though - I DO recognize that the knowledge you possess and teach Is many years of experience 👍 SO being 60 years old myself - and a DIY mechanic ( generally) I GREATLY APPRECIATE YOU and your KZbin video’s ✌️

[@ScannerDanner]

Thank you so much!

[@GeminiSeven43]

Thanks so much Paul and Danner for another great video. Lots of good tips and it is great when we get to see you go through cases like this that might not make sense at first but through knowledge of basics you show us how to interpret the data and come to a solid conclusion and fix. Merry Christmas to you and your families and I wish you a wonderful holiday. Thanks so much.

[@JimmyMakingitwork]

This is one of the things we always have to weight in the shop. How many hours, or how much further testing should we do, vs a fairly inexpensive part to test. Always a balance and what matters most is understanding the systems and when to do this type of diagnosis. Great work as always.

[@Pablo_Automotive]

Thank you Paul for another great video where persistence and data clearly showed the fault, I take this opportunity to wish you and your family Merry Christmas wishing you the best

[@darrendesmarais8124]

Merry Christmas to you and your family Paul. Another great video on fuel trims. Thanks.

[@mikeburdi3464]

Another great video and teaching moment! I totally agree with your call on the MAF. All of your data was pretty much pointing in that direction and then once seeing that it was an aftermarket sensor, I was convinced that was going to be your problem. Great call and you are definitely not a parts changer! Sometimes we have to weigh out the cost of a part versus another hour of diag just to end up back at the same place. Well done Danner duo! 😅

[@alexisjohnson9608]

Another great and informative video. Happy Holidays brotha Paul.

[@miclewis55]

I watched your fuel trim videos many years ago and learnt an awful lot from it . Use that info every time I have a running fault on a petrol engine …. thanks for the $$$’s sir. 👏👍😀

[@waqasazmat81]

Paul hope you guys have a good Christmas and as always many many thanks for educating us. Caleb thanks for helping your dad by editing videos and posting it for all of us.

[@ScannerDanner]

Blessed to have my son working with me. Thank you!

[@danielgeng2306]

Thanks Paul and a very Merry Christmas to you and the family !

[@onemechca]

Thanks Paul. Merry Christmas to you and family. Merry Christmas to the entire SD community.

[@raymondmetcalf9110]

Cheers you guys I need to learn more on fuel trims at 70 love it.

[@nelsonnarciso1791]

Good thing I own a 2008 sx4 all wheel drive . Good to bank this one into my suzuki vault of repair data. Thank you. Merry Christmas to you and your family.

[@Drescars]

Rich and lean codes are a pain!! But you always mail them… thank you for another great video, I learned so much just watching your videos!!! Merry Christmas to you and your family and a Happy New Year!!!

[@ScannerDanner]

Thank you and Merry Christmas to you too!

[@shepherdsfleetservicesllc8147]

I want say that's great thing you added it with humble mechanic on tool box build. Merry Christmas and God bless. Hopefully next year our company and help with it.

[@lloydwakefield9040]

GBY All!🙏❤😊Thank you for bringing uncommon knowledge to the common people❤😊

[@mike-yp1uk]

I love the pre-inspection. I pull a code and look under the hood. This is the perfect time to fix oblivious damage. I get cars with partially installed air tubes or bad rodent damage and diag time goes down drastically. This technique is good for seeing the types of systems the car is using. ECT... Sometimes they will have a repair free by the dealer tsb or bulletin. You get burned and then you start to look first before you cross that street. Lol I love what this channel has to offer a technician who wants to better themselves.

[@ScannerDanner]

Thank you so much!

[@nancylewis7142]

Thank you for all this information.

[@James-fs4rn]

👍 you guys are the best! Happy New Year!

[@alexfriedrich9874]

Thanks danner. All the best to you and yours.🍻

[@careyautorepairs]

Amazing video. Thank you Paul.

[@georgepranis5183]

Would have been interesting to see the wave form with the sensor ground. Love your channel!

[@bradfaught1695]

merry christmas danners...hope your staying warm

[@CHARLYNNE123]

This was a hard complicated diagnostic well ✔️ done

[@simonparkinson1053]

48:10 Absolutely! Once I have determined sensor ground is intact, I always use sensor grounds as reference when scoping. I love the independent channel grounds of the Pico 4425 for this reason and cringe when I see people lumping all those grounds together on battery negative. Maybe they do it because Bernie said it so many times? But with a common ground scope, that's all you can do. While peak detect on snap-on can be useful in ensuring fast signals are not missed on a long timebase, it can lead you into seeing problems that aren't there - you're probably seeing the radiated signals from secondary ignition under load, which will be filtered out by the ECM.

[@williamgagnonroadboxservice]

Can’t say enough about the things you SMA And Pine Hollow have given to me this year. It’s Christmas everyday from you guys. Thank You so much!! And Stay warm Merry Christmas to you all and your familys

[@ScannerDanner]

Both great channels and good friends. Thanks so much!

[@jackiemay9471]

merry christmas paul and family

[@Kingsleyintech]

I thank you for learning new things

[@Portuguese-linguica]

Caleb great job filming and editing. Paul & Dan great job on being cool dudes and the service you provide.

[@ScannerDanner]

Caleb is the man. Thank you! Merry Christmas

[@petar443]

Merry Christmas and happy new year 🎄

[@subieracer005]

HumbleMechanic said to check you out... so I did.. good stuff!

[@ScannerDanner]

Thank you! Charles is awesome. Glad your here

[@angusproud1971]

Since this was an engine out rebuild look for rags stuck in intake, had one with a blue towel stuck against MAF screen causing rich condition due to higher air velocity thru MAF from restriction. I saw you pulling airbox and was just waiting to see this.

[@thhc1744]

Merry Christmas to the Danner clan.

[@ADSautoDiagnostics]

Great video for my class, i am like you, 3rd year automotive instructor at Southern alberta institute of technology in Alberta Canada, I always teach the importance of understanding Fuel Trims, Thanks Paul FERAS

[@ScannerDanner]

Thank you!

[@bmpn155]

It'd be nice if we could somehow put together a known good MAF reference table everybody could contribute to. Year, make, model, engine, intake air temp, idle rpm, coolant temp, and mass airflow amount. I think it'd be especially helpful on the smaller engines and forced induction stuff. I know I've seen on some of Bernie's videos where they have a VE database built into their diagnostic system on vehicles they've collected the data on but it'd be nice if we had just a general reference at idle for everybody to look at.

[@Turbotomass]

Service information has specifications for engine performance parameters.

[@bmpn155]

@@Turbotomass Not for everything, also a lot of DIY guys aren't going to have access to service info

[@ToddErickson365]

I made an Excel document to calculate G/Sec when I worked at Identifix Asian Dept. docs.google.com/spreadsheets/d/1ZF0zIhZW6VPhw7S-D41zm_uRoLi2kTwJAlP_iiOoSm8/edit?usp=sharing Let me know if the link doesn't work.

[@mentals555]

@@ToddErickson365 hey man I requested access with the link you posted

[@ZoomAutoDiag]

Awesome description of the process to get to the final result. Nice work as always and thanks for posting the video man.

[@ScannerDanner]

Thank you!

[@robertmobileman8304]

Merry Christmas to you and your family, your brother would make a great santa claus ! Lol happy holidays

[@ScannerDanner]

He would!!

[@tracydiller9378]

Great video Danner boys as always.Call me a parts snob but OEM all the way been there to many times with after market parts especially with Todays Technology.Everyone have a Merry Christmas and a safe and Happy New year.God Bless.

[@Ashroyer86]

O.e. is original not o.e.m.

[@tracydiller9378]

@@Ashroyer86 OOPS My Bad!!!!😁

[@bobparsons391]

A great video. Thankyou

[@IamReadyToRock]

Thnks Paul, from Peru

[@raymondmetcalf9110]

Cheers you guys found that really interesting love watching your videos when you get your teeth into it and won't let go. Fuel trims.

[@ScannerDanner]

Glad you enjoyed it. Thank you!

[@00jake00]

I seen the CRC can come out and I'm like ummm that stuff ain't flammable........ know that becuase I did the same thing just a few weeks ago😂. Great video as always.

[@ScannerDanner]

Lol filming live has its drawbacks. Thanks!

[@portlander7280]

On cars with vacuum brake booster system, when I’m going to make the trims go to lean from the driver seat on engine idle I just push the brake pedal few times and that does it for me. And yes it depends on what I’m trying to chase and which PIDs I’m trying to look at. Merry Christmas everybody

[@majicdude88]

Danner’s bro got a backwoods blunt wrap in his shirt pocket. Nice. Blowing trees lol

[@ScannerDanner]

Lol, it's just tobacco

[@frankoattes]

5 mins in and I’m thinking it’s maf! I’m thinking this because I already had a similar issue, but it was over fueling. No codes in the system but the maf reading was around 4.9v. Cold , sensor was clean! I took one from another vehicle and it solved the issue. We had this car sitting for a month with one of the techs just throwing parts at it! I had a look at the data and notice the maf reading were not as per the reference values. Sometimes it pays to read your shop manuals when looking for no code faults just to see if anything jumps out at you. I was lucky to find this, I think the other techs frustration made him lose his thought train.

[@user-cx5lw2xm8x]

Thank you for video

[@harrylister804]

On my Toyota 2.4L, the g/s at idle is right around 2.2-2.8. In my case, the g/s is very close to displacement at idle. I don't like my Total fuel trims though, edging up toward +10% at idle. I'll inject a flammable in the intake and see which way the trims go. I had a very brief stumble at start that cleared up when the weather got colder. Thanks for the videos, lots to learn, much to apply.

[@ScannerDanner]

If you're under 10% you're fine. It's possible you have a small vacuum leak if it only is that way at idle.

[@harrylister804]

@@ScannerDanner Thank you, SD. It could have a vacuum leak at idle and then the problem is masked while driving? I took my scan data and used max RPM and MAF, IAT and atmospheric pressure and calculated volumetric efficiency and got 110% VE. I blame the fantastic videos you put out loaded with information. I'm doomed I tell ya.

[@mike-yp1uk]

This reminds me of the time we had a car and they put a federal emissions engine in a California car the intakes were a bit different which gave us a slight idle problem and code.

[@nasirkamal7560]

great video great explanation. lots to learn and over view. you mentioned alot about calculated load value. can you please elaborate more. thanks merry christmas to you and celab.

[@ScannerDanner]

Thank you! It's a mathematical calculation that is highly proportional to whatever the MAF is indicating (as you saw). But it's basically throttle angle, RPM, MAF and MAP (if it has one). I believe BARO is also involved and then the VE of the particular engine.

[@nasirkamal7560]

@@ScannerDanner Thanks Mr. Danner. But i was trying to say that if the calculated value of load is identical with maf plugged in and unplugged then nothing is wrong with maf. But if they are not identicle, as we saw in case study , then maf is skewed. Is that right assumption? Thanks

[@mysoap23]

I work for suzuki in New Zealand the maf sensors on these older sx4 with the jb20 engines and the suzuki swifts with the m13 m15 and m16 engines are very common to crap out

[@boboften9952]

Thank You Paul Thank You Caleb Thank You Brother Danner

[@calholli]

So many links. I feel like you're wiring my brain into the network matrix of your channel like I'm a cyborg. lol.. Love the rabbit holes.

[@ScannerDanner]

Hahaha thanks for watching my friend

[@zimouzimou5725]

Thanks 👍🙏

[@jamesjobe927]

Hey over the years I’ve been going through all your videos, including premium, wondering; how this same scenario would play out on a speed density engine with an aftermarket map sensor? I would love it if you could talk more about that style. I have a Subaru I love that I just can’t give up on, but have struggled to learn enough information to identify the problem.

[@ScannerDanner]

Chapter 8 (psi sensors) I would cover testing MAP accuracy. Thank you!

[@ovidiumonoranu367]

Thank you for these very instructive videos. I'm a newcomer on your channel, you are a great teacher, and I think this is what I was looking for! What about fuel trim diagnostic strategies for cars that have MAP Sensor instead of MAF Sensor?

[@ScannerDanner]

It's no different, but vacuum leaks certainly effect them differently. I have some classes on that. Maybe even one here on KZbin. Check my chapter 1 playlist. I'd be there if I have it.

[@ovidiumonoranu367]

@@ScannerDanner Thank you! I have checked out the chapter one playlist on KZbin and unfortunately I think there isn't. But, please, what do you mean by vacuum leaks affect them differently.

[@ScannerDanner]

@@ovidiumonoranu367 too long to type out, as it is very complex. I have lectures on this one my website if you can't find what your looking for here. This one in particular www.scannerdanner.com/scannerdanner-premium-chapters/chapter-1-universal-testing-methods/chapter-1-universal-testing-methods-full/202-chapter-1-universal-testing-methods-pages-9-13.html

[@ovidiumonoranu367]

@@ScannerDanner OK. Thank you!

[@ScannerDanner]

@@ovidiumonoranu367 of course!

[@rockynix7731]

You where being tested on this one Paul .. they thought they was going to but a good one on you .

[@christophergraham9726]

Hi Paul great channel we need more like you on the planet. Can you tell me why there was no movement on 02 bank 1 sensor 1 after fix please.

[@ScannerDanner]

It's a wideband so they don't move the same way. When I used global data you could see the rich lean swings. I think I showed that in this video? Thanks!

[@jwoeltje6949]

When I was looking at the scan tool data I noticed you had key on engine off you hadn’t started it yet. It showed 1. point something grams at the Maf. I know Toyota had a TSP back and I think 2005 or 2006. It would help if you look at grams per second key on engine off and if it was outside of that specific number the MAF was bad.

[@tomaszukal5426]

Hi Paul 🙂 awesome work you are a Legend, your work is INCREDIBLE 💪 I believe every cheap fake part is sweating and shaking when you see 🤣🤣🤣.

[@ScannerDanner]

🤣 thank you

[@user-tb5vc4vm6l]

Hi Paul, I'm an electrician, with electronics repairer knowledge. I don't have access to good scanner. I have simple OBD scanner. This scanner allows to do some advance programming on GM vehicles. ABC blead, Crank Position sensor, Transmission diagnostics and more. I have 2002 Chevy Avalanche 1500. Truck was sitting with blown engine sins 2006. I replaced engine (I drove the donor on parking lot). I replaced the tranny with remanufactured one (old tranny has antifreeze in side). Take truck for inspection. No pass. No check engine light. Technician sad that truck need MAF. No check engine light. It can be seen on scanner. Trouble shooting steps: 1. Cleaned MAF. Code pop up after 15-20 min drive. 2. Replaced MAF from good running truck. Code pop up after 15-20 min drive. 3. Stop by other local shop for diagnostics. The technician replaced MAF with new AC Delco MAF. ($150 MAF and $350 labor). Code pop up after 15-20 min drive. Technician sad tis is wiring problems. 4. I check continuity from MAF connector to PCM with tester and with test light (under load). Ho wire damage. Good ground. 5. Check PCM connector, MAF connector, check wiring - move the harness with engine running. Sprayed water on intake manifold, throttle body, No effect. 6. Replaced PCV (PCV was bad). No effect. 7. Replaced AC Delco MAF with new AC Delco MAF. Code pop up after 15-20 min drive. 8. There 12v on Pink and Black wire. 4.5v on Yellow wire. (this 5.3l has cable TB). I "jerk" the throttle - voltage dropped from 4.5v to 4.2-4.12v on Yellow wire. 8. I checked O2 sensors (they new Denso). I connect OBD dangle and see graphs on my phone. All 4- O2 sensors acting healthy. No misfire. 9. I reassessed PCM. Goes throw the learning prosses. Code pop up after 20 min drive. Now I run out of options. Is there any suggestions? Or any good diagnosis you can recommend? I'm on NY.

[@ScannerDanner]

What code?

[@Z14kt12timandjes1]

Really good video! Anyone ever seen this? Well maintained 2007 Camry had a p0101 code & system rich 5 months ago. Total trims around - 40. Pwrs/Grounds good, no vac leaks, pcv good. Replaced MAF with Denso made in Japan & that fixed it. Best fuel trims I'd ever seen on my wife's car, around -2 total trim. I keep a bluetooth scanner connected each time I drive her car so I monitor trims multiple times per week. They stayed GREAT. No codes, no issues. Ran like new. 5 months later, same codes re-appeared while my wife was driving car. When she got home, I hooked up my scanner to check it out and the fuel trims were correcting.... as if the problem was fixed.... but I didn't fix anything, didn't touch anything. Long trim was -20, Short was +20, "correcting" for whatever the problem was all by itself. I've been testing everthing I can think of, and driving the car daily for 5 days and the problem is gone again. The only difference I see is, now total trim is a bit higher.... around 9 under load, around 5 at idle. Any experience or guidance would be appreciated. I'm a home DIY-ing Dad, but a long time student of ScannerDanner's book, premium, and youtube content. Paul (& James) have taught me a lot so I would probably describe my skill level as high on understanding and knowledge of what ScannerDanner teaches, but low on actual experience working on a lot of cars, as the only issues I ever get to work on are my family's cars, which I take care of so they don't normally have many issues. Thanks for any suggestions.

[@ScannerDanner]

You'll need to catch that problem when it is happening. It's pretty difficult to make a call when the system is correcting and the problem isn't currently there. Thank you! Pretty awesome that you understand what the counter fuel trim numbers mean!

[@Z14kt12timandjes1]

Thanks. You're an excellent teacher.

[@dimisrambodimisrambo7285]

all suzukis after 2005 show code p0130 for the o2 sensor and rarely show a code for lean or rich mixture. whenever we have such a code we always look at the fuel trims to tell us if the o2 sensor is at fault or not. at 7.30 in your video you do the test by pressing the gas and leaving it, there the sensor first goes lean and then rich until it goes to o ma. but the o2 sensor is fine

[@corryarbuckle1314]

Just a thought: if there's a frequency analyzer on the scan tool you might find out that there's a specific frequency responsible for the "hash" on the MAF signal. This does not look like random noise but specific signal pulses. Maybe the firing of injectors is responsible for the hash.

[@ScannerDanner]

This hash is really everywhere in a car. If I'd have used sensor ground you wouldn't have seen it. But the main reason you did was with peak detect turn on, on my scope, it is sampling that screen 6 million times. If I farted you'd see it with that sample rate lol

[@cardiaglexia995]

Thanks for your video but i can' t focus you didn' t say your grandson is fine??? Your best videos with your brother he is a great man .merry christmas to you and your family.lg.

[@ScannerDanner]

Granddaughter and yes, she is doing well. Thank you!

[@cardiaglexia995]

@@ScannerDanner thank you paul that was important to me i prayed god is with us.

[@alexlongpre4527]

Hey Paul,, great flick as always. I have a question for you. At around 27. 45 you mentioned "let's go to the graphing meter" When do you want to use the scope vs the graphing meter and vice-versa?

[@ScannerDanner]

This wasn't a great example of when to switch to the graphing meter. I just wanted to see what it looked like with a longer time base, without worrying about the scope sample rate (peak detect) I'd say in short, I don't use the graphing meter very often these days unless I'm looking for a glitch or drop out on a time base longer than 5 seconds. Or if I want to graph a voltage trace that is a constant signal that shouldn't change and I'm looking for a glitch/drop out I'd definitely use the GMM for that

[@alexlongpre4527]

@@ScannerDanner thanks you very much for taking the time to answer in details, it is much appreciated. I'll add that to my book of tricks. Happy holidays to the Danner family and long live this channel.

[@harry8145]

So i have heard of Maf Initialization being perhaps required for Mafs for sprinters it seems a hotly debated subject in sprinter forums with no conclusive yes or no .I have 2006 t1n replaced maf oem and it wont run unless Maf unplugged still , turbo wont kick on etc ,after watching some of your incredibly interesting lectures i tested voltage ,ground ,sensor ground and sensor signal all good but it still fires and dies ,then i heard about initialization perhaps being nescesary , vehicle is getting 2068-4 Maf faulty on/off ratio of reference signal is outside permissible range , i wonder if Initialization would adjust this and does it need to be a mercedes dealership to accomplish this , am glued to your inspiring lectures, thank you, if i was a little younger .....

[@canadatransistor]

i like to use volumetric efficiency tests to rule out crappy MAF sensors. It's too bad the tires were flat - couldn't take it out for a rip.

[@pecata01]

Seeing the scanner actually display an equivalence ratio, that's actually the most accurate output from the wideband sensor. EQ ratio essentially is lambda, so for example 0.95 lambda (13.965:1 AFR) in open loop means a -5% trim will bring it back to stoich mixture. And vice versa, if it's at 1.05 lambda (15.435:1 AFR), it will need a +5% trim to get it back to stoich.

[@ScannerDanner]

it's just another O2 data PID that can be false when there is a sensor malfunction

[@pecata01]

@@ScannerDanner I agree, but for this specific case the EQ ratio works better than the O2 mA. Great video otherwise!

[@lolipopdeck3694]

Pual can you do volumetric efficiency test in this case ? And as always it's a pleasure to watch you do your magic

[@ScannerDanner]

All of the VE tests I know how to do are with the throttle wide open. I'm not aware of any closed throttle VE tests that are valid. Though I'm sure someone out there has some formula 🤔 thanks!

[@lolipopdeck3694]

@@ScannerDanner yes i know it only at wot So u could do the ve test wot in this case right ?

[@ScannerDanner]

@lolipopdeck3694 you could but it probably would have passed that test. The issue with skewed sensors is there are times within the range where they'll read properly.

[@rudy2298]

Happy holidays sir ! I wanted to ask on how you can find out right away on whethere high voltage on the scanner graph means rich or does it mean lean on this particular vehicle, and does it change from vehicle to vehicle ? Thank you so much for all your videos

[@ScannerDanner]

It changes from car to car. They do not all report the same way.

[@rudy2298]

So that's where your WOT test and deceleration test come in handy to figure out ! Ok i see thank you so much Mr. Danner you are a huge help

[@ScannerDanner]

@@rudy2298 you got it! It is a way to force full rich and full lean to then gauge the signal of the sensor

[@rudy2298]

I got confused because i wasnt paying attention to where on the video the b1s1 pid is displaying amperage, too where the other b1s2 pid is displaying voltage ! That's why on one the graph goes up and the other goes down on deceleration test

[@shepherdsfleetservicesllc8147]

I love the video. Which scanner was that I know it was snap on.

[@ScannerDanner]

The Verus Edge

[@shepherdsfleetservicesllc8147]

@@ScannerDanner we have solus legend

[@deebalt071]

Good find. I agree with MAF’s are the hardest to call or take a gamble with. I’ve got lucky a few times and also not so lucky. But on another subject. Dealing with a 03 Ram that has a single misfire during decel. Full tune-up has already been done due to carbon tracking on plug. Injector also replaced to see if that was an issue. Idle and normal driving is fine. Any ideas on what to look at or test? Thanks if you can shed some light.

[@ScannerDanner]

During decel, the injectors are cut off. What does a decel misfire feel like when non of the cylinders are firing?

[@deebalt071]

@@ScannerDanner change of tone in engine. And misfire counter in scanner showing dead mis. Can’t physically feel the misfire which is odd.

[@deebalt071]

@@ScannerDanner figured it out. Used a pressure transducer and saw something going on with the exhaust side. Put a scope in the cylinder and saw the valve had worn into the head and rounded the seat.

[@deeznutz3494]

Maybe someone already mentioned this, but look at 19:45 right before you took the scanner data off the screen; your grams per second jumped to over 20! I’d have been sold right there I haven’t dealt with widebands a whole lot, but I remember from Chrysler training that mV should be around 450, and less than that is lean and more is rich… Or maybe is this the setup that 0 is stoich, -1 is lean and +1 is rich… or something like that??

[@nickayivor8432]

Merry Christmas 🤶 🎄 🎅 everyone 🎄 PRODIGY Sir ScannerDanner My teacher Sir ScannerDanner Thanks 👍 God has bless you PRODIGY Sir ScannerDanner Caleb thank you great 👍 👌 From Nick Ayivor from London England UK 🇬🇧 ⏰️ 17.09am

[@priestlygarments4004]

My 2009 Honda Accord Stalled 5 years ago After I Drove Through High Waters But After A Few Tries It Started Again But With The Engine Light 5 Years Ago And Was Told The Catalytic Converter Is Bad, That’s The Code That Comes Up. As I’m Driving Sometimes Exhaust Smells Permeate The Interior Which Smell Like Rotten Eggs. Also Somehow I’ve Managed To Pass DMV Inspection 4 Years Straight With A Check Engine Light & Bad Catalytic Converter. What’s crazy is that this year I failed the DMV EMISSION TEST 4x and then I went to a shop and asked them to clear the codes and prayed and when they checked again at the DMV it passed 😂. This year they were strict but prior years they weren’t even checking! The dealership says I have Low Compression On The Number 4 Cylinder & P0420 & P0304. They say the engine was at 60psi. They performed the diagnostic in July. I heard Cataclean cleans the catalytic converter. I saw it on Amazon. What do you think? Is That Bad Catalytic Converter Endangering My Life?

[@ScannerDanner]

Fix your misfire first before ever worrying about CAT codes. Also the rotten egg smell is not from a cat that's failing, it's from raw fuel being dumped into the cat. Most likely from the low compression cylinder.

[@priestlygarments4004]

@@ScannerDanner oh wow you’re the man! How long can I drive like this? I’ve had this issue for 5 years and somehow I keep passing inspection

[@ScannerDanner]

@priestlygarments4004 hard to say, it certainly isn't healthy for that engine or the cats to continue to drive it with a constant misfire. It is a constant misfire right? At 60 psi of compression it has to be. I'd recommend unplugging the injector for that cylinder.

[@priestlygarments4004]

@@ScannerDanner Oh wow! What about my health? Should I be worried of carbon monoxide? Cause Honda is asking for 6,000 to put a used engine 2,000 for a used cat. I don’t even have those funds at the moment. I paid them to diagnose and all the lady said is that it’s not worth repairing to just buy a new car 🤦🏽‍♂️. I regret driving through that water trying to pick up an Uber rider. 😂 The car moves very well bro just the TPMS LIGHT is on and the engine light is solid. They said the TPMS sensor could be dead because the tires are perfect. Just those lights are on! Everything else is solid. I failed the DMV emissions test so I just had the dealership clear the codes temporarily and it passed.

[@user-mu3nv7xx2l]

Dear Paul, hello! I'm fighting now with Subaru. Engine was swapped from 1.5 A/T to 2.0 M/T, there was a lot of mess and misconnected wires. Looks like i've fixed wiring problem. But i still cant fix what is wrong with MAF. I have a new original MAF sensor. And i have around 4 volts full throttle. But my grams per second readings are 12 grams at idle, and 400 grams full throttle driving test, average 2.0 atmospheric engine. I've thought ECU was from some turbo subaru, or was re flashed. So i've bought a used ECU for this engine, and, i see the same readings. FUnny that my injection pulse at idle is 2.8 ms, it doesn't look like 3 or 4 times more. And, no backfire in exhaust. I can start engine warm, if i've had a 3-4 time more fuel, i would have drowned engine with fuel and never could start it warm. Also there is Bosch 5 wire LSU 4.2AF sensor. Reference 2.55 volts wire was swapped with pumpig current calibration wire, so my AFR was constantly 0.69 without any chance to go rich,Only lean. After i've fixed wiring problem, i have 1.0 AFR until my front AF sensor warms up, then i get -20% short term instantly, and my rear O2 sensor goes lean, low voltage.SO i assume wrong readings for my front AF sensor. But. also i have now 35 kPA at idle, it is higher than it should be. Maybe i have a good AF sensor now, but i have plugged exhaust? or Valves are not sealing combustion chamber properly? Or my AF sensor after thousands KM o fwrong connection damaged?Is that possible?

[@ScannerDanner]

Let's move this to my forum www.scannerdanner.com it is free to join and we can try to help you there. When it comes to engine swaps, especially to a different size completely, things get complicated and I can't do this here. Too much research to do by myself to help you. Thanks! Hope to see you there.

[@CarlosDiagnosticos]

That noise is caused by a problem with power or ground supply for the sensor. Maybe a fuse or just old wires. You see that a lot on cheep cars.

[@carlosm7232]

Why do some cars not show you the upstream o2 voltage?.. But instead show you the current, i never understood that and always have a hard time diagnosing because of that

[@ScannerDanner]

Only wideband oxygen sensors report like this. And with them comes a huge variety on what the scan data pid actually reports

[@mauriziogiasan4411]

super ❤️ .top 👍

[@MidwestToolReview]

Hello ScannerDanner, I need your help and advice!! I'm a diy'r, but with above average mechanical skills and general knowhow...lol. I'm looking for a pro-grade scanner, but want to save some $$$. I've allotted $500 for a scanner, but I want to ensure I have full...or near full diag capabilities with respect to being bi-directional, and the ability to scan and reset systems. Which brand would you recommend and why?

[@ScannerDanner]

The topdon phoenix Lite, hands down. But you'll be spending around $900 for it. Though topdon is now offering a less expensive unit that is not bluetooth but would be tethered and it goes for around $500 but if don't know if it's "full function" like the phoenix

[@lisandro12349]

Im randomly getting codes p2198, p2098. Also same for the other bank (2196,2096). on a 2010 Audi S5 V8. I do also get P0141 sometimes. I get LTFT -8 to -17 at most for both banks usually a bit higher for B1. Replaced OEM injectors, carbon clean, low pressure fuel pump and filter, low and high fuel pressure sensors. Plugs, coils, HPFP and pre cats O2 sensors replaced about 55k kms on it. MAF is original, I tried another one with same results. I even check the Evap purge valve. Downstream O2’s seems to be working fine, both reading about .60sh to 70sh. I removed them and cleaned. What else I could check? I want to to a flags tune on the ECU. 🤷‍♂️btw, cars runs great with lots of power it’s just those codes coming once in a while. Sometimes if I do startup and rigth away drive only trigger p0141 heated exhaust gas.

[@ScannerDanner]

Your first mistake was replacing all these parts based on these codes without doing any testing. Now you've added additional variables (bad new parts) to the mix. Define all the codes please.

[@Jpilgrim30]

I’ve never had any kind of luck with aftermarket mass airflow sensors that have that blue and white chip style resistor. They never read properly.

[@jeremybrewer3289]

Less then a 3 liter engine you say cant use the rule of thumb with g/s based on liter of engine. I understand that as I use it. But question is will a smaller

[@cheatjoc742]

Hey, at 44:30, the downstream O2 sensor is sitting at around 0.8 V. Is this cause for concern? From what I can tell, I don't think its an issue because you still have good fuel trims. Is this a bad sensor? Is this a normal reading? If anybody has any insight I would really appreciate it! From

[@dimisrambodimisrambo7285]

IF WE DID A VE TEST DO YOU THINK WE WOULD HAVE A BAD VE FOR THIS ENGINE? COULD A VE TEST GIVE US A DIRECTION?

[@Sonichu_is_watching]

I think it's time to get Bernies Escan with the volumetric efficiency calculation.

[@briansmobile1]

36:16 See, with the B.B. leak you have to abandon the Maf unplug it test for the vacuum line plug it off or pinch it test. lol

[@mlp8500]

Question I got a Buick 3.8 supercharged Buick park ave and I have a p0172 I checked the term #s and seem to be ok. What can else can I look for? Thanx ..appreciate any tips

[@ScannerDanner]

What's the freeze frame data of that P0172 code show you for STFT, LTFT, ECT, RPM, ENGINE LOAD?

[@christopherwoods9830]

how is the calculated load determined?

[@philh9238]

Suzuki that’s your first problem. Surprised the snap on had it since they’re not made anymore. I always watch diagnose Dan basically widebands are reverse of narrow band

[@rodericktolliver977]

I have a 20008 grand marquis it idels high until I put it a gear then It doesn't wanna accelerate after a little while I've changed spark plugs Coil packs cleaned throttle body kinda of Lost atp do you think it's my TPS ) throttle position sensor or what would you think the problem is ? Anybody!?

[@RR-bt5xv]

i have seen you clean throttle body for high engine load does that not apply in this case?

[@ScannerDanner]

For high TPS%, not an engine load PID. Also for a false MAP sensor code

[@briansmobile1]

22:22 There you go! There's a bug in the system! lol

[@ScannerDanner]

Stink bug for the win lol we actually have a video where that's what it was. Nice to hear from you Brian!

[@DDR233]

So why isn’t the upstream O2 sweeping from .1 to .9?

[@stisti8431]

My subaru forester 2.5 xt is overfeuling black smoke only on normal operating temperature start up not doing it on cold start its doing it for about 5 sec then smoke disappears do yoz think its maf?

[@ScannerDanner]

Maybe an engine coolant temp sensor issue? Any codes? What year is your car?

[@shawnsharpe1912]

The old smack on the component test has definitely worked for me. Especially, on Mitsubishi MAF sensors.

[@AAA-br3cs]

Sir in this after replace maf o2 sensor2 is going up700mv .my thinking that it reading should 450 mv.750 mv means that's system is little bet rich but fuel terms are normal .plz explain

[@ScannerDanner]

An upstream O2 should be switching from 200-800mv and it is normal for a downstream O2 to be steady

[@diamondstateautodiagnostic5250]

Hey I got a question this may be a little bit off subject but since we're talking about oxygen sensors on foreign cars like Hyundai's Hondas does the downstream oxygen sensor play a row in the fuel trims I have noticed several times that the downstream oxygen sensors fuel trims will be 99% and we'll never change from thatBut if you look at the downstream oxygen sensors on OBD2 or under Hyundai you will notice that they are working but the fuel trims r still stuck at 99% a lot of times I've never really wrapped my head around this

[@ScannerDanner]

when you see downstream fuel trim at 99%, this is a data parameter that is not being use. Also, I have never, not once, seen downstream fuel trim being used with a narrow band upstream O2. Only some systems with wideband upstreams will they also use a downstream fuel trim strategy for minor corrections. In my chapter 4 and 5 playlist I have a case study on one with downstream fuel trim control. Thanks!

[@diamondstateautodiagnostic5250]

@@ScannerDanner thanks for the reply I really appreciate it I would love to get your book just been a little short on cash here lately I believe the car does have wideband upstreams anyways like I said thank you sir appreciate the info

[@ScannerDanner]

@diamondstateautodiagnostic5250 oh no man I wasn't suggesting you go and buy my book I have playlists right here on KZbin that correspond to the chapters in my book but that's all, you don't need the book to benefit from this. here's the playlist I was talking about kzbin.info/aero/PLD2809EEC7BAAF989

[@diamondstateautodiagnostic5250]

thank you sir I really appreciate that one of these days I really would like to buy your book and join your premium Channel I love watching u videos I don't even watch TV anymore I just come home and watch your videos LOL maybe one of these days I can order a book from you I'd love to have a signed copy LOL

[@ScannerDanner]

@@diamondstateautodiagnostic5250 I can do that 😉, just sent a signed one to the Uk Email me at [e-mail] when you want one. Thanks again!