2007 Honda Accord Wideband O2 (Air Fuel Ratio Sensor) Testing

This Honda came in with a P0171 and a P0420 trouble code. Join us as we show you how to handle testing of a wideband oxygen sensor, also known as an air-fuel ratio sensor.
Videos and playlist mentioned:
Wideband O2 sensor testing, P1130 (Lexus RX-300) part 1
• Wideband O2 sensor tes...
Wideband O2 sensor testing, P1130 (Lexus RX-300) - Part II
• Wideband O2 sensor tes...
(Chapters 4 and 5) Fuel Trim and Oxygen Sensor Testing
• (Chapters 4 and 5) Fue...
(Chapters 4 and 5) Fuel Trim and Oxygen Sensor Testing
• (Chapters 4 and 5) Fue...
• How to quickly test an...
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.
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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.

[@evanwynne5293]

I have worked for Toyota and Honda and both 4 wire planar type widebands work with opposite mA readings. The only way to truly know is to look at the cars technical information. With Toyota's denso type AF+ sits at 3.3V and AF- sits at 2.9V. The difference of 0.4V is lambda 1 which is 0mA. The change in voltage produces the electromotive force that changes the current value. +A = lean and -A = rich. With their denso system in their diesel engine the concept is the same but the voltages are 2.2v AF+ and 1.8V AF-. I will have to dig out my notes on the honda stuff to get the exact numbers. Great video thanks👍

[@ScannerDanner]

Thank you so much! After quite a few comments about the opposite amperage, I didn't have a really good answer, but I knew I had it right. This gives me peace of mind. Really appreciate you jumping in here.

[@evanwynne5293]

@@ScannerDanner no thank you Paul. Without finding your videos back in 2015 and getting your book I would have never gotten the thirst to pursue diagnostics. With your help and dealer training in 4 years I was able to become a Hyundai master tech/High Voltage Tech and Toyota/Lexus diagnostic tech. You inspire a lot of new techs out there keep up the good work and thank you all the way from Ireland 🇮🇪👍

[@chekelley6861]

Makes sense! I love networking. Even if it’s just on KZbin 🤣

[@ScannerDanner]

@@evanwynne5293 this makes your comment even more awesome, I'm serious man, for a minute I was questioning myself and my analysis. Thank you do much for giving back. You truly put my mind at rest today because service info on this model sucks! They give you absolutely nothing in Mitchell and some Google searches just show a bunch of articles claiming the opposite with authority and I'm like, but, but 😅

[@evanwynne5293]

@@ScannerDanner my pleasure! Glad to be able to help. To be honest the technical info that Honda give is not great even on their Maris system. Toyota seems to be a lot more comprehensive but even that has thrown me for a loop on a few occasions. Had a Prius with low voltage codes in a couple of units, techdoc said to change converter with inverter assembly for the particular code. Was intermittent and seemed to be very specific to a particular drive condition. Would happen after the customer overtook another car. Found the main grounds for the control units that showed low voltage codes were shared with the indicator on the left side of the car. As he would use the indicator the voltage would rise on the bad ground enough to flag the codes. Once he cycled the ignition the problem would be gone. Replaced the grounds and the problem never resurfaced. Again all thanks to following your steps👍

[@andrewwmacfadyen6958]

If you aren't a scope user make the jump, apart from.your brain it is the most important and most universal diagnostic tool.

[@spankranchgarage]

We’ll put. I agree

[@ziadabdelmuti9547]

When ever I change a o2 sensor or maff sensor or a/f sensor I disconnect the negative battery terminal and reset the fuel trim then do the drive pattern in all readiness mode to see if any codes come back. This is another great video I learn a lot from I appreciate you for posting it and always look forward to more great content from your videos!

[@BTCAutomotiveTech]

I teach the use of the Equivelance Ratio PID on Global OBD2 for this diag. While the mA may be contradicting on different makes, the scale and direction of the EQ ratio PID never changes. Also handy - there is usually a “Commanded EQ ratio” and an actual “EQ ratio” PID.

[@alieutaal459]

The best people on this planet are those with knowledge and willing to share it with others. You are definitely doing your bit Sir. Thanks for what you doing. Wish you and your family well.

[@ScannerDanner]

Thank you my friend

[@notsponsored103]

Next level editing!!! Putting that much care into all the detail in a video this long is totally amazing!! Cuts, B roll, multi channel video layers, all beautifully trimmed and sync'd. Incredible. Just incredible. wait, and out takes!!

[@ScannerDanner]

Nice! Sending a screen shot of this comment to my son

[@ScannerDanner]

Caleb and I are constantly learning and improving and trying to bring you guys the best videos. Really, thank you for this comment. It means a lot.

[@calebldanner]

thank you for the comment, friend. It means a lot

[@Hondaflip]

Great stuff Dan a lot of learning like always. Hondas do read their perfect fuel trim at 1.0 volt and lambda indicating rich below 1.0 v and lean below 1.0 v. These accords also tend to leak right at the intake tube where you had the leak after replacing sensor just fyi. Thanks again for a very well detailed video

[@DJ-tn7vj]

The videos over the years got tight. Thanks to your son for holding it down all these years. You never know, he might be the next person to produce another movie.

[@ScannerDanner]

agree, just read this to Caleb too, thank you!

[@chriscadman5715]

Excellent video. Thanks for sharing it. You always make a very complex subject look easy!

[@ScannerDanner]

Thank you!

[@abdelhaditiaaza8511]

You are a great teacher, thank you very much scanner danner🙏

[@Paul1958R]

Caleb/Danner/Paul Another great teaching video - thank you! Paul (in MA)

[@Pablo_Automotive]

I love theses kinds of videos, thanks a lot team Danner.

[@ScannerDanner]

thanks Pablo! my longtime friend :-)

[@georgebell3964]

Always more questions than answers When you’re repairing a car. Great video

[@ScannerDanner]

Anything I can help clarify?

[@Rusko1DUB]

I have same question, I suppose the fixing was when hose was plugged in intake, but still car has positive trim cause of dirty cat, the cat is clogged by rich mixture that engine use when the hose was removed

[@patriot2164]

Another great Video , Thanks , Love learning !

[@ferrarif174]

Looking like TRIPLE H from the side great contents like always

[@donniejohnson7499]

Awesome video Paul.

[@spelunkerd]

This video was a real challenge for my dyslexia, I had to pause and watch the first part three times to wrap my head around the numbers. What I hear you saying is what I expected, that when lambda is > 1.0 the sensor is detecting a lean condition, opposite to narrow band where higher voltage numbers mean rich. At the same instant the lambda is +1.5, the current is -0.8, and the two data pids consistently swing in opposite directions, so negative current must be a lean signal back to the PCM in this Honda. That's confusing, but easy enough to remember for Honda. It sounds like it might be easier to remember "Large Lambda Lean" in all cars to recall which way lean pushes lambda. In terms of the response of the PCM, the fuel trim readings are in the SAME direction as a narrow band, ie greater than 1.0 fuel trim means the computer is responding to that lean observation by adding more fuel, like it did with narrow band. In the end, I'll have to play with the scan tool in every car to see how these sensors are calibrated, while driving it rich and lean with snap throttle or induced vac leak. Thanks for the detailed walk through!

[@pcb4041]

Thank you for the great knowledge!

[@bobflannagan7262]

Well well well. That was amazing. After you replaced the sensor and the numbers still weren't right I was hoping you would use the exhaust gas analyzer again for a truth check. I know you didn't need it but would have been interesting and fast to do.

[@josedejesusvelazquez6863]

Hi Paul, whenever you show a video like this, I always learn a lot from your teaching. I really enjoy them. As always receives the biggest cyber-hug. from Tijuana B, C. Mexico. 🇲🇽 👍👍👍

[@ScannerDanner]

Thank you Jose!

[@josedejesusvelazquez6863]

Paul, let me recommend this video of Mr. Bill Peack, which is related to the case that you present here. from Tijuana Mexico. 🇲🇽 I hope it is useful to you. (4 Wideband Air/Fuel Ratio ((AFR) signal values and Scan Data) Note: this video is in KZbin.

[@ScannerDanner]

@@josedejesusvelazquez6863 post the link my friend

[@josedejesusvelazquez6863]

@@ScannerDanner kzbin.info/www/bejne/oHfXY5iYms6FopY

[@ScannerDanner]

@@josedejesusvelazquez6863 good video, but just keep in mind this is A design, and not all are exactly like this. He's discussing a 6-8 wire sensor and using a Toyota example with the 3.3 and 3.2 bias. This Honda design is just not like this at all. 4 pins and opposite ma numbers. Lots of variables with these for sure.

[@paulfiebke3909]

Love this one keep up the good work and God bless you and your family

[@ScannerDanner]

Thank you my friend

[@cyberslacker5150]

I like it that Danner finally is embracing the Autel over the Snap-on. Great video.

[@ScannerDanner]

At times yes, at other times no 😀

[@Sagittarius-88]

I've used both, and there's a bit of a misconception among the autel fanboys that their scanners are the official "lower priced replacement for snap on scanners". Absolute nonsense. The autel scanners do a lot of things well on certain vehicles, but the exact same can be said for snap on. There are no magic bullets in this business, nor are there any "one size fits all best of the best scanners". It's simply a matter of selecting the best tool at the time for the task at hand.

[@gerigesquiere66]

Many thanks Mr. Danner.

[@85jmccoy]

I havnt used a 5 gas analyzer or seen one in a shop since I graduated U.t.I. back in 08.... always wish I had one they are very useful.

[@stefanmyszkowski5306]

In Toyota systems with A/F sensor from Denso, the difference between AF + (3.3V) and AF- (2.9V) is constant = 0.4V. Only the current value changes. Only the current value in [mA] informs about the A/F (or lambda) ratio. Very interesting video Mr. Paul Danner!!

[@ScannerDanner]

And these will read opposite of this Honda

[@andyclemente4205]

Awesome video.. the thumbnail is the best part 😂😂

[@LAW-fv6ys]

Great video! I've learnt Euro and Asian cars need clearing of codes which resets the fuel trims also, after fixing any fault. A test drive also helps to relearn everything back to normal after. However bmw and mini are different resetting/clearing codes doesn't reset learnt adaptions for fuel trims, GDI injectors etc, you need to delete the adaptions with a suitable diagnostic tool or even better inpa or ista SOFTWARE. I've just encountered this on my bmw 325i with gdi after nox sensor failure and 1 piezo injector which was failing lean when hot only. After coding new injector and resting all adaption with inpa I followed the relearn test drive process and now runs perfectly. Bmw also use wide band sensors showing 2volts for lambda 1 stociometric with 3volts being rich and 1volt lean for up stream only and narrow band for downstream 0.45v is perfect 0.9v is rich 0.1 lean.

[@salvimeca8678]

Great video , would be great if we can get more videos on wide band sensors

[@ScannerDanner]

I'll film them as I see them my friend, thank you!

[@jarrodlethborg7942]

Great to see the autel in action

[@LeewardStudios]

My 2006 accord had that persistent +12 short fuel trim. Checked O2 sensors, fuel psi, MAF and for leaks. The air pipe from the MAF to the throttle body had small cracks on the bottom where it “accordions “ . Only found it when I removed it to clean the throttle body. Ordered OEM and bam numbers went to +2. Got me thinking. Looked at my 1999 accord, same cracks. Unless you remove the pipe and gently pull it apart and look you will never find them. BTW the 99 has a short term, long term combined of +1.5, with 280k miles I’m fine with that!

[@PaulCTownsend]

Great info on the function of the Wide band Sensor.

[@ScannerDanner]

Thanks Paul! Keep in mind, this is not a standard here, there are others that operate with opposite polarity

[@PaulCTownsend]

@@ScannerDanner I don't quite know what that means.

[@ScannerDanner]

@@PaulCTownsend on this Honda, a positive ma number is a rich signal, on other models a positive ma number is a lean signal

[@bbkmm1]

I had exactly the same failure on a 2007 Accord. The code is down stream O2 sensor stuck rich. Lucky I had 2 Accords and swapping the down stream O2 sensors didn't make a difference. Unplugging the upstream sensor did the trick.

[@HotRod-wv4vm]

Thanks for the video

[@joebagofdoe4762]

Wow, Great Teacher!

[@isalmankhan1]

Awesome intro👍

[@ScannerDanner]

I'm glad you like it

[@markferraro5250]

Great on SD. Lovin it.

[@AntonioClaudioMichael]

What a Great Video And Demonstration Great example of a lying O2 Great catch ON this one @ScannerDanner

[@loreleipetit9429]

I would do a cap burn to clear out adaptation then drive. For the newbies, that disconnect the pos. and neg. terminals and touch them together to discharge the capacitors in the pcm to reset the values

[@AntonioClaudioMichael]

Autel Ultra Is a Beast of a scan tool love that scope can be used wireless from the data Link

[@PaulCTownsend]

Sometimes you have to do what's best for the car and let the chips fall ware they fall with the customer. Poor oil is not helping the car or the customer. Great info.

[@Z14kt12timandjes1]

Fuel contaminated oil could affect fuel trim? I didn't realize that. Good info. Thx

[@georgebonney90]

Thank u mr danner 👍

[@billsullivan8812]

@ScannerDanner- Happy New Year Paul. Well , I think this might throw my theory out the window at wide open throttle, watching the voltage on a wide band sensor should decrease slowly over the time the vehicle is driven at wide open throttle , then increase when foot is taken off the gas indicating the wide band is operating correctly. Thought I had these wide band sensors figured out, perhaps not!😂

[@ScannerDanner]

Just remember that wideband sensors and how the manufacturer displays the data for them, are not all the same! The signals can be opposite of what you think or of what you've seen before. I do believe that when the actual milliamp numbers are given, that positive is lean and negative is rich, just like we saw here. But when voltage is given, this is a processed valve and the numbers can be whatever the manufacturer wants and they are definitely not all the same.

[@jameslewis1175]

Paul, Question: If I take my test light from my positive batt term to an unhooked power dist center and it lights and vehicle never blows fuses. Is that from hot switch circuits?

[@m.b.smoshitoa8325]

Hi Paul , you thought us many things but you never explained you do you identify if the o2 is narrow band or wideband. Mbs moshitoa ( south Africa)

[@fire7765]

Good job

[@AntonioClaudioMichael]

Very interesting diag

[@BlazeGelos]

I did a toyota in which unplugging the battery did the fuel trim reset, the fuel regulator was allowing about 5psi extra pressure than spec and somehow the lambda sensor was reading lean, and even with a new sensor it did the same, like if the amount of fuel was so much that it messed up the reading, anyway, the original sensor was dead and changing the fuel regulator and resetting the fuel trims repaired the fault.

[@mandytuning]

I use an aftermarket wideband gauge clamped on the tailpipe to compare when in doubt

[@codylopez2020]

Where did you get your prescription safety glasses?

[@TheBeamerGuy_]

What scan tool are you using? Looks like genuine honda

[@mahmoudomar5190]

Egypt loves you 🇪🇬😍

[@hamedzakiii4140]

Hello I just bought an autel maxis 909 diognoistics tool and I wanna learn how to use it can you make a video about it?

[@butbut948]

which model of your autel diagnostic instrument are you using???

[@frankjohn4302]

Thanks Danner

[@jamesgoularte8460]

check the front motor mount some run on vacum, just pinch the house and see if the fuel trim goes to normal

[@fredshead3956]

I used to use gas analysers all the time cuts out all the crap and you can see what what the exhaust gasses really are, i used to use a Sun engine analyser in the old days, made in Crystal lake Illinoi, and i am in England..

[@throttlebottle5906]

the editing at the start had a "max headroom" feeling about it. :))

[@ScannerDanner]

🤣

[@monsonlockandkey]

Got the safety glasses on when working with Autel

[@christiandiaz7422]

Hey Paul I have a question for you. On material that I have read and on some of your case studies says that negative current is rich and positive current means lean but in your scan tool you it appears only negative current flow, why does that happens?

[@ScannerDanner]

It is on SOME, not all my friend. Read the pinned comment from a friend, right here in this comments section. Thanks!

[@thebestever333]

I didnt have any codes except the catalyst code, so I changed it, however the light came on again, and my sluggishness persisted. Hills that I used to take with ease are now difficult especially in hot weather

[@davidgregory7702]

don't be a parts changer!

[@edwardroca9140]

Hello sir! From Vigan city, philippines, what should be my first step in checking my corolla 4afe, dont start but has a spark in the spark plug socket only the color is orange . . Engine check light is not steady. . It goes on and off . . What would I do sir? I dont have a scanner sir

[@marktirabassi7160]

What autel scanner is that your using ?

[@Ironblank1]

My car has a v6 engine First code was p0430 this after I parked the car for maybe 3 weeks. Then later the code p0101 after maybe 6 months on the road. I cleaned the MAF sensor and went away for maybe a month and came back. So I took it to gas station they said it went away by itself. 2 days later check engine came back, this time it was a different code p2099. I pulled the code and check fuel trims all of them fluctuating around 7 or 8%. Today I took it to gas station the guy said needs catalytic converter. He just looked at the scan tool saw the same code p2099. Is the guy right about the converter? Can you help?

[@jamesbond2187]

i always rode around with my primary a/f sensor unplugged after i got the heater code but i have a KTUNER ecu [[ kpro for 05-06]] so it was already tuned and ran fine without it now that i did a TSx swap i guess the intial start up needs the 02 sensor because its suck on 14.7 on the tuner app and says OL_FAULT, Plus both fuel trips read 0 at all times if i go past 5% tps the car stalls out will this on sensor cause all these problems where i cant even get the car out the bay door ??? 05 rsx wideband

[@carloshernandez2216]

You forgot to check fuel trims on global after the fix, just to compare with your current data, great class

[@ScannerDanner]

I didn't feel it was necessary as we learned how to interpret the factory data earlier in the video, by using global data. No reason to go back, but it would have driven home the point better, sorry

[@stevebryson2459]

Great

[@jamesmichael7311]

Honda wants you to reset the ECM and do an idle learn after AF sensor replacements.

[@GraditelMacedonia]

If is posible AUTEL to coloring thats number green, yellow and red to easiest recognitions of what nubers are normal, close to specs and what program does need/ask and what is out of specs.

[@ScannerDanner]

Videos and playlist mentioned: Wideband O2 sensor testing, P1130 (Lexus RX-300) part 1 kzbin.info/www/bejne/bYnQY6WPhr2HbtU Wideband O2 sensor testing, P1130 (Lexus RX-300) - Part II kzbin.info/www/bejne/qWjdp2yrr9hjmJY (Chapters 4 and 5) Fuel Trim and Oxygen Sensor Testing kzbin.info/aero/PLD2809EEC7BAAF989

[@lukas181118]

Wideband o2 we measured current flow in mA not volts. Positive current -lean condition , negative rich . 0 current means afr14.7 or lambda 1 .

[@ScannerDanner]

Positive current on this one was a rich signal. Also watch when the system was in decel fuel cut mode. The sensor went even more negative

[@ScannerDanner]

watch at 35:53 when I had the MAF unplugged for the best view of this, both downstream and upstream sensors are full rich in this moment (new upstream sensor) Lambda is opposite, but this is just a calculated number anyway. Lambda = 1.0 and numbers below are a rich indication and numbers above are a lean indication

[@ScannerDanner]

Read the comment I just pinned by @Evan Wynne, we have an answer 😉 Thanks!

[@otiliohernandez8349]

What Autel do you were using?

[@ScannerDanner]

I believe it was the Ultra

[@tracydiller9378]

GRUMPY DANNER LMAO!!!!!Great video guys as always until next time PEACE.P.S. Yes mike him up.

[@AntonioClaudioMichael]

I would think the reason it's still dumping fuel makes me think it would be dirty maf or A Erratic Af Sensor 🤔🤔 wonder if cat is super saturated because of the amount of fuel going through it

[@chekelley6861]

It would be interesting to see another scan tool used to measure the sensor current. The discrepancy with negative vs positive current and rich lean could be a scan tool issue.

[@ScannerDanner]

Read the pinned comment by @Evan Waynne

[@randyr.parker2698]

"Why are you seeing blurry" Bahahahahahaha, I feel your pain!

[@throttlebottle5906]

you're seeing fuel cut off happening, with every hard rev and release. it seems the sensor is working, but skewed way off.

[@ScannerDanner]

It was weird in that it would react to a lean condition but not rich

[@andrewthompsonuk1]

I have found wide band sensors harder to deal with because the calibration strategies are non intuitive. A wide band sensor does not have that switching point so they need to do something else to calibrate themselves.

[@Sebastianx115]

Does anyone know what kind of wire piercing tool that is

[@speedy_pit_stop]

Great case study but how can you work like this 25:25 ? haha.. Global Data??? What did I miss??

[@avtoelektrik_volgograd]

👍

[@PaulCTownsend]

Recheck the tailpipe emissions. Then change the oil anyway cuz it was too rich.

[@MarioDallaRiva]

Paul, at 36:04 you stated -69% lean as its showing 0.69 I would think if 1.0 is effectively zero, then 0.69 would imply -31% lean (0.69 minus 1.0). Have I been drinking too much grappa with my espresso? ie moonshine

[@ScannerDanner]

😅 totally misspoke there, great catch! You are correct. Thank you!

[@MarioDallaRiva]

Aww, you were testing to see if we were paying attention . Yeah, that's the ticket!

[@ScannerDanner]

@@MarioDallaRiva 😉

[@msntung]

Was that the B1S1 that he replaced?

[@ScannerDanner]

It was the upstream oxygen sensor (S1=sensor 1=upstream of the cat)

[@otiliohernandez8349]

I got confuse!I learn that negative current at the upper fuel ratio sensor mean rich. Did I got wrong information?

[@ScannerDanner]

There is no standard for that. This model it is opposite

[@jygogaming3550]

Wide band and narrow band are differents

[@phunhonla2484]

+-5 can be mass airflow dirty, others should not him, or the acceptable error from old sensors. +6 to +20 pumping case can be fuel regulator or fuel pump (pressure check important - use manufacture data documents/ Alldata), -5 to -20 can be injector leak or regulator too high (pressure check important). over +20 need check by smoking test (maybe gas cap, Evap system, brake booster leak...) or just lock all split air hose, it will easily figure out. Data memory is never needed to reset due to supper fast PCM re-action. if the memory of long trim is +49 and all problems are solved, the -48/-49 should appear immediately in short trim. So confident with what you see on real-time data. PCM is never wrong but sensors can lie. DIY doesn`t have too many bucks to change and to try on everything to tell which was wrong. So do the smart way with correct logic and correct analysis will save a lot.

[@zochpeter]

gas analyser after shot, please please, please! you have it on the table, why not take the readings after_????

[@ScannerDanner]

Sorry 😞

[@AVCONSULTTX]

​ @ScannerDanner Wait, negative wide band current =reading lean? My Pilot and every other car I've measured with a wide band sensor, negative current = reading rich. Why the opposite on this vehicle or scan tool?

[@ScannerDanner]

Good question my friend. You're the third person to mention this. My answer is I'm not sure, but you could clearly see it was operating this way. The decel fuel cut (definitely a lean period), the ma numbers were negative, and when I had the MAF unplugged, and the mixture was pegged rich (new af sensor), you could see the ma numbers were postive

[@ScannerDanner]

Read the pinned comment from @Evan Wynne we have an answer

[@PaulCTownsend]

Test drive the car full throttle uphill if possible. Then recheck the rear sensor.

[@rick343]

My wife's 07 Accord gets a PO420 code that will cause the engine light to come on for a couple of days and then go away, for weeks and then come back for another couple of days and then go away again for weeks or months, no other codes just the PO420, any ideas?

[@ScannerDanner]

Yep, you need a cat Make sure you do not have any exhaust leaks and fuel trims are normal and no other codes. Use a factory replacement ONLY! Aftermarket cats will set this same code again in just a few short months

[@rick343]

@@ScannerDanner Question, if I took it off and hollowed out the inside and put it back on, will it throw a code? We use to do that in the early 80's when they would clog and cause loss of engine power. The wife's car is running perfect, can I use a temp sensor gun and keep a check on how hot the pipe is before and after the cat to see if it's getting worse? Just wondering.

[@hotboy11452]

ScannerDanner i have 2 dodge calibers different years "2007 and 2012" but both have the P0420 code and both have bad Catalytic Converter i did the same as you i replaced both o2 sensors on both cars and both smells like rotten eggs.. long story short i don't have "$1,018 each" for the catalytic converters.

[@ScannerDanner]

Rotten egg smell is NOT from a bad cat. It is from a bad mixture going into a cat. What are your fuel trim numbers?

[@hotboy11452]

@@ScannerDanner well i can't tell you on the 2007 it's off the road for some time till i can get other things fixed but the 2012 is the car i'm driving when it showed the engine light it had a s.t. of 1.3 and l.t. of 3.9 but i had to bust the Catalytic Converters on both and get 2 new exhaust manifolds for both the Catalytic Converters where stopped up and cracked them.. they got very hot

[@brianbrassington6385]

hi good day i have a suzuki swift k12b 2011 it is running full rich -35LT and -25ST can u help me PLZ

[@ScannerDanner]

What is your downstream oxygen sensor indicating? Need a voltage reading

[@brianbrassington6385]

Voltage is 0.46

[@brianbrassington6385]

How can I send u a video from the scanning tool directly

[@HotRod-wv4vm]

Data is the android on startrek

[@hlq2action310]

Holy sh** what a thumbnail for this video 😀

[@ScannerDanner]

🤣 my mom hated it

[@JimmyMakingitwork]

In the flat rate world, once I saw the rich rear reading and lean front, while smelling rich condition…i’d unplug the front sensor or induce a vacuum leak to test next. They are usually asking me how long before I can look at 3 more cars….:).

[@ScannerDanner]

agree, in the flat rate world and even in my brothers shop, this thing is getting a new AF sensor based on just a few checks with scan data. When we started, my brother had already ordered a sensor. I just used this opportunity to go over some things with you guys

[@d.d4184]

I have been following you for 8 years. As I have said many times you have helped me make a lot of money. I found this video very hard to watch /concentrate on with all the editing. Zooming in and out plus the jumping mid sentence. I understand that your Son is trying new things out to bring us the best possible experience. This one just didn't work for me. Off to watch it again.

[@ScannerDanner]

Taking this to heart my friend. You are not alone and Caleb and I have talked about it.

[@d.d4184]

@@ScannerDanner I have watched every video you have ever made. This is the first one I have had an issue with. Thanks for taking this on board. Keep up the good work please.

[@ScannerDanner]

I think you're the 4th or 5th person in this comments section to say something about it, and to be honest, I didn't notice how aggressive the cuts were until it was pointed out, and now I can't un-see it. So I'm in agreement. Mainly the parts where I'm in the car and talking with you guys. But we're always, always looking to improve and we appreciate you guys so much, including this type of constructive criticism!

[@d.d4184]

@@ScannerDanner you can't un see it😂😂. I can only imagine how much hard work goes into the editing. So thank you for not taking offence. You guys are doing a brilliant job.

[@ScannerDanner]

@@d.d4184 Caleb and I spent so much time together on our newest video kzbin.info/www/bejne/f4TYlImCrdaaipY I've been waiting to hear from you because we really talked about and fixed so many things, right in line with what you were saying. There are still some jump cuts, but they are in areas where it was necessary. I'm anxious to hear your thoughts after you watch it. Keep in mind too, when you are looking for them, you are going to see them. Something Caleb and I had to keep in perspective during the edits of this one

[@Sophie333C]

Why are you not using the equivalence ratio?

[@ScannerDanner]

If the sensor is wigged out, how is a data pid that is a mathematical calculation based on that sensor going to help me any further? Serious question. Maybe I just don't know how to use it as I should be?

[@Sophie333C]

@@ScannerDanner if equivalence ratio greater than 1 you have a lean condition, less than 1 you have a rich condition!

[@ScannerDanner]

@@Sophie333C but if the sensor is skewed, that data PID will be also, so I guess I don't really see this being a major value to us in this case. Thanks!

[@tyhoang63]

Don’t wideband sensors add current when rich, not when lean? So the graph should go down when WOT and go up on decel. Opposite of a narrowband.

[@ScannerDanner]

On this model, I dont know if this is all of them, positive current is rich and negative current is lean

[@ScannerDanner]

watch at 35:53 when I had the MAF unplugged for the best view of this, both downstream and upstream sensors are full rich in this moment (new upstream sensor) Lambda is opposite, but this is just a calculated number anyway. Lambda = 1.0 and numbers below are a rich indication and numbers above are a lean indication

[@ScannerDanner]

Read the comment I just pinned by @Evan Wynne, we have an answer 😉 Thanks!

[@tyhoang63]

@@ScannerDanner great video. Always learning from you. - a young tech from Toronto Canada.

[@guccimane5752]

I thought for a/f sensors negative numbers mean rich?

[@ScannerDanner]

There is no set rule for that unfortunately. It is opposite on this model.

[@ValeriosD]

Isn't -mA indicating rich condition on wideband o2 sensors?

[@ScannerDanner]

apparently not on this one my friend, I'm looking for a better answer for you guys 🤔

[@ScannerDanner]

Read the pinned comment from @Evan Wynne, we have an answer!

[@tharakanuwan9986]

The vehicle specific information is paramount to solve this kind of problems. I remember the Go Tech channel did a great video about these type of sensors. Mike Becker (host) said always treat every vehicle different. I can also remember Scanner Danner doing a video on Lexus having a bad AFR sensor.