P0420 Everything You Need to Know - Subaru or Whatever You Drive!

Here's an Amazon link to that impact gun → www.amazon.com/gp/product/B00B...
This is the O2 Sensor socket I used in the video → www.amazon.com/gp/product/B003...
Connect with me socially on these social media spaces
Facebook → / briansmobile1
Instagram → / briansmobile1
Twitter → / briansmobile1
Who's the BOSS? Get'em to donate here! It's tax deductible! These folks help
kids like my daughter to stop having seizures so they can develop properly!
Glut1 Foundation → www.g1dfoundation.org/ways-to-...
briansmobile1 where do you live? What's your address? Can I send you a sticker or product? Sure.
Here you go!
My mailing address → P.O. Box 282 Cedar Valley, UT 84013
P0420 Everything You Need to Know

[@michaeledwards2919]

It's so great to actually watch and listen a technical mechanic who knows exactly what he's talking about. Excellent video. Thank you.

[@dwaynetruhlsen8321]

I can't believe I watched this whole episode on the catalytic converter, just because he was actually interesting. Good job man!

[@jenfugit7801]

22min later, I'm still glad I watched! Thanks for the overly informative and fascinating video!

[@patrickzadd5215]

I’m an ASE Master Technician I always learn something from your videos. thank you, Brian!

[@justinhuskey8651]

Awesome! I love the way the information is conveyed. Understandable, with technical points and some light humor. End result information to spec and the reason why.

[@billyr9840]

I dissect a lot of things myself, but I never thought of that one ! Great Vid !

[@jonathanflynn618]

This was great, so glad I tuned in!! Now let's go skiing!!!

[@northernswedenstories1028]

This video has it all. Probably the only one I've found that actually diagnoses this code correctly. Also you have a nice view from your garage!

[@elijahapuna8869]

Excellent presentation I finally realize what exactly is going on inside converter and got an idea on diagnosing.thank you!

[@coopercraft]

Brian thanks so much for this video, it helped me a lot, I have an 04 Outback with the EJ259 and CA emissions that was running like crap, I ended up needing all new AF and 02 sensors as well as a new exhaust with new cats. The Car has 259k miles on it I believe the motor was rebuilt at about 180k and at some point around 225k the sensors failed which probably is what caused the cats to burn up. Nothing lasts forever, but after all that was fixed it runs really good again. Really appreciate your videos so I hope that fills your tank a bit!

[@bekomcar554]

Brian, big thanks for sharing your experiences

[@hammerhead6537]

Thank you Brian. Very interesting. Your videos are always entertaining and educational.

[@emtscythe3782]

Excellent Video Brian. I'm actually directing one of my customers to this video that needs a Cat replaced on his Sebring. Thanks.

[@albertomorillo168]

awesome internal operation!!! now I have the brightest idea what's inside the catalytic converter, keep it up bro!!!

[@wyattoneable]

Interesting break down. It's cool to see what's inside. I liked the voice overs too. Thanks for keeping us straight.

[@leetos.4915]

This is by far the most interesting deep well insight explanation of details of honey comb inside a cat converter that I found on yt…appreciate u brother for sharing this with us…you’re definitely worth more than a precious metal!

[@silkytp789]

Love the inquisitiveness. Always educational. Thanks Brian.

[@DENicholsAutoBravado]

Thanks man. I needed a nap. The video was super extra good. Grinding and cutting just puts me to sleep when that's what I need. :) Cheers. In my limited experience on replacing cats usually aren't melted when they're bad so it was lucky you got share that on top of a good fix. P0420 and P0430 are my favorites. They're my first codes I learned to fix and I claim I'm expert on them and all the ways a car can be wrong, that they're actually good. Not that this is a complete list, but exhaust leaks can set false P0420's as random volumes of air can enter the exhaust via venturi's. These centuries aren't consistent so it can simulate the stoichiometric wave pattern of an upstream O2 sensor. Stuck O2 sensors upstream can cause larger fuel trim adjustments, which can set P0420's or 30's in seconds, though usually more time is required.

[@DENicholsAutoBravado]

Of course AutoBravado, when you've replaced catalytic converters you've only had one which could be seen through without a cut down. Be sure to recycle the old catalytic converter for money. I know of a man who used to fix exhausts until he found out he could make more money cutting out the precious metals to sell as valuable scrap. Haha

[@joelmccoin9727]

Hello Brian, Another great video, Educational, informative and entertaining. Many Thanks

[@briansmobile1]

+joel mccoin Welcome Joel! Great to see you!

[@garym5161]

This guy really knows his stuff, thanks.

[@bobbydejesus5987]

Great video! You're great at this man. Thanks!!

[@almfreak]

Man i love how much detail you go into and that you explain the science behind this stuff. Great video, thanks for your quality of work and quality of channel!

[@christopherbaum7083]

On my 2004 Subaru Legacy 2.5 I spent a lot of money on diagnosis and O2 sensors as well as spending time trying KZbin quick fixes. In the end, got both cats from Rock Auto (Eastern Catalytic) and they've worked fine for over 10K miles. The Rock Auto price was around $600 and I got $60 from the junk yard for the old cats. Subaru wants about $2000 for the cats. OEM are undoubtedly better, but I'm not sure they are three times as good. My originals went about 120K miles before the P0420 showed up. I was able to jury rig the old heat shields into place. Seems as if they would be important. Also used exhaust insulation tape to replace the old insulation between the heat shield and the exhaust pipes. My car is manual transmission and the Eastern Catalytic converter had brackets that I assume were for an automatic. Some strap steel and pipe clamps enabled another jury rig and have had no further issues. This took me 8 hours and for the money I saved I made over $180 per hour for my time. I also learned that you can spend a lot of money on diagnosis and O2 sensors trying to save money on catalytic converters.

[@ricksalazar6637]

Brilliant! Thanks for taking the time to explain!

[@gjonesii]

Man you really know you stuff and how to explain it. Thanks man.

[@ManicMechanic007]

Awesome, thanks for taking the time.

[@eflanagan1921]

Breakdown of function is fantastic !

[@berniepokorski2489]

Once Again, Great Stuff, Brian!

[@RockwildazFamily]

Thanks, think this made me fully understand that I most likely have a clogged CAT. Audi B8 which had piston issue causing oil leak, that was fixed but it seems the oil leak may have caused the honeycomb to burn out & get ashy in the CAT.

[@johnferguson7235]

Nice of you to take the time to deconstruct the CAT. Thanks for adding the explanation of the cause for the excess unburned hydrocarbon in the exhaust. Few people understand that excess hydrocarbon cause over heating and CAT failure. Did the owner first repair the compression problem or did they want you to throw on a new CAT so they could sell the vehicle as is? By the way, there is a couple hundred dollars of precious metals in the converter. I hope you have a place that takes them in trade.

[@jimv1484]

I watch vids for hours every night and for some reason I feel this is one of the best vids I have ever watched. Awesome job and nobody could ask you to be any more thorough than that! I guess this is an old vid so I doubt you will see my questions but I will try anyway. How many miles did that Subaru have on it and is their a somewhat typical mileage where the cats get clogged? I have a 2006 Subaru Baja with a 2.0 JDM dropped in by the previous owner. The car bogs in second gear and doesnt like to climb hills......the JDM I am hoping was installed and converted correctly........but the shop I just took it to I assuming that the cats are clogged. I have 183K on the exhaust system........One clue is the engine sucked in a baseball indent on the air filter....nobody has ever seen that before but seems like it is pulling air hard. So I ordered a cheap ebay cat section to just have the shop run it with free air flowing to see if that solves the bogging problem. What aftermarket cats do you recommend for Subaru 2.5 's? Thank you

[@DanijelTeofilovic]

This guy is great! Thanks for your effort.

[@waynes.2983]

thank you for explaining this. my daughter had the same car and I cleared this code twice in the last 2 months. Looks like a simple fix that I can do at home. Only question is...did I see you install the new cat with no heat shield on it? or did I miss something?

[@candicedavenport2982]

YES IM GLAD I TUNED IN! lmao thank you, sincerely me and my struggling subaru

[@MrCDRWilson]

Awesome video! Learned a lot in this one. Thanks :D

[@billburkart9087]

I'm 60 plus years old and enjoy your videos.

[@spooky4e]

Cool video Brain Nice to know all this stuff

[@JF0913]

Thanks for sharing your knowledge!

[@AaronsAutomotive]

Brian, in the opening with the machete, well it's used in automotive service the same way my wood splitting maul does, as an extra too... My maul has seen more metal than wood I believe, the back make for a great BFH!

[@keithkennedy4859]

good tips brian..another way to check is tap on the outside of the converter with a rubber mallet..if you hear that rattling its broken.

[@vaultman88]

Excellent video, as always! Also relevant to me as well, as my jeep is throwing a code about my cat. So with you down south now, you hitting up Brian's Head? I'd love to board some mountains surrounded by red rock. Also, you ought to make something nifty out of that old cat! The way that thing melted is almost artistic.

[@philipcooper4375]

My Xterra has 4 catalytic converters, for the price to change them I found rebar as a great alternative, combined with a piece of electrical tape to cover the check engine light with

[@foihdzas]

Great vidjea! This happened to my 04 sun fire. Car wouldn't rev past 3500, cat was all broken apart and blocking the exhaust like you mentioned. A sawzall fix it!

[@charlesneves9656]

Your video is great! Your personality is awesome and I dig all the hidden jokes in the there - plus I'm learning : ) High five buddy!

[@ravi270783]

nice and very informative video. if you have time, you should make a video on how to weld a universal aftermarket cat in to it. dont know the success rate on those though.

[@mds19238]

Excellent job, thank you.

[@61066clocks]

Enjoyed the vid..good stuff

[@mikec1096]

sweet. great video brian. thanks

[@clhchp6900]

Cool like the fact that you show it step by step. Im a woman and i like learning about parts on cars.

[@SchrodingersBox]

One thing about that chemical equation is the consumption of O2. This can be used as a diagnostic advantage. On the scantool pull up the S1 and S2 O2’s on the suspect bank. If the cat is working, then obviously it consumes the incoming O2, therefore S2 must show fixed rich. If the cat is not efficient, then the incoming O2 is not consumed- it will be identical to the S1 trace since nothing is changing! Confirmed diagnosis of activity or failure of catalyst.

[@billyr9840]

+Schrodingers Box - Matt, You were probably wetting your pants when you saw them dear equations ! LOL!

[@SchrodingersBox]

Billy R Hahahaha almost- Organic Chem not my thing but still appreciate a balanced equation!

[@billyr9840]

Schrodingers Box LOL !

[@cent31119]

Great video with excellent detail and explanations. One thing tho, what about metal vs ceramic core catalytic converters? What is your thoughts about them?

[@dmain37]

Perfect timing! I am just ordering Headers (with CAT Pods built in) and the rear CATs for my 2006 Nissan Titan due to the P0420. Non-Sequiter: I see you fly Radio Control stuff, BUT, do you also Metal Detect!?? :-) Thanks for the great work you do and share. If not for your VW brake video, I never would have attempted on my bug.

[@ludesup]

Hi Brian, great video and great topic, keep up the good work. Also just want to ask why is it that this video is in 480p? most of your other videos are in 1080p. thanks

[@jtech23]

Great video!

[@randallalton6310]

I had the p0420 for years on my 02 Outback. Eventually I ended up with mysterious fuel delivery issues, chugging loss of power. Replaced the upsteam O2 sensor and it fixed both. Bad upstream sensor can confuse the catalyst reading.

[@joemiele1296]

New spark plugs and 2 cans of BG 44K squashed my P0420 Code. 2014 Nissan Sentra SR 160k miles. Good luck!

[@emmahaskell8644]

Thank you! You should write the repair manuals! Finally someone that actually explains things like we don't know what we are doing! Thank you! 😊

[@robertchristopher2447]

Thanks for doing this! I know I asked if maybe you could go over this a while back and I think it helped me... now I know I need to drop all my money on a new cat. For an 02 forester, what brands or companies do you trust enough to recommend a new cat?

[@MatthewEMarsh]

Awesome video. Now I actually understand that my P0420 code probably is a truly bad converter.

[@neverstoplearning382]

thanks for taking the time great info

[@glennjoslyn385]

Thanks for the video! Cool Hat by the way! Glenn from Hawaii

[@jonathanfloyd335]

Hey man, love your videos, thank you! Working on a 02 llbean with 200000, not sure if cats ever been replaced, but it’s throwing a very intermittent po420, cleared on its own. I don’t have a live reader to check 02 sensors, and I don’t just want to throw parts at it. Subaru said it’s pretty straight forward on the phone and said it’s the cat.. where should I start? Would o2 sensor be intermittent or would cel stay on? Any advice would be huge. Thanks boss!

[@jhlewis10]

Thanks for the Video. I am getting the P0420 also, my O2 bank one sensor is steady while the bank 2 sensor is all over the place, have a hard time believing a 2013 vehicle needs a new cat!

[@DIYApprentice]

I'm assuming you took it to the dealer. What was the diagnosis? Which car?

[@garypersons9320]

GREAT video! I have wondered for years what the inside of the catalytic converter looks like. My truck threw a _0420 code a couple of weeks ago I am told that that code is strictly for a bad cat. Any possibility that it could be a bad O2 sensor as the cat was changed last year when my shop found a cracked exhaust manifold.

[@enriquev8832]

So cool!! Thanks for sharing

[@haywardsautomotive6156]

Nice video Brian!

[@stella2033]

Mines toast I'll be having to switch mine out, very good video !!

[@kuuzer]

hello from stormy Ireland. idea about taking the sensor out to feel for cat blockage is something I'll remember 😉

[@nickolaguez]

I love your approach. Skillful, Sarcastic, curious and in some ways philosophical. It's much appreciated! Thanks for quenching my curiosity as well. Ps: know where I can get a cat for a sulev accord? I'll pay ANY amount for a new one, but I can't seem to source it 😢.

[@elithe240guy]

Thanks for this!

[@eddiejclayton1]

What brand is that new cat (it looks really nice), I'm having the same issue with my 2007 Impreza with 200K miles on it. Awesome video, thanks so much for recording/sharing!

[@caseherm]

eddiejclayton1 2006 Impreza orbs with 200k. What did you figure out? I have lots of stuff in my amazon que: gaskets, o2 sensors, cataclean, new headers/cat, 02 debunker. Torque wrench, pb welder lol jk already had that. Thinking about going down to one cat. What was wrong with yours? Did you dissect it?

[@classic287]

What an excellent video. Explanation of how the catalytic converter works and cutting it up so we can see what’s inside. Very good...

[@alexturcotte8589]

Awesome ! Learned a lot :)

[@gwho]

21:20 the diagnostic methods are the most helpful.

[@DIYApprentice]

Well done, sir.

[@albertomolina8682]

Excellent video.

[@zoomzabba452]

Title made me laugh because of how much a nightmare tracking down a P0420 in a Subaru is. Good info.

[@briansmobile1]

+Sean Black Thanks Sean, do you feel like you could do it with a scanner now having seen what the numbers are for a bad and then a good cat for the rear O2 sensor? Bad cats fluctuate from .01V up to 1V when the engine is warmed up, and good cats hang out at .7V with dips every so often at idle after they're warmed up.

[@LeavEyeDDrum]

Subbed. Thanks for all the info!

[@emt1581]

Did you replace the gaskets when putting in the new cat? I know you said you were holding the one on with your thumb. Thanks!

[@3dombee524]

awesome and informative video!

[@rd946]

Hey, Brian, using the non-contact temp probe, what is an acceptable temperature differential between the inlet and outlet of the catlytic converter? I've heard about 100 degrees, but wondered if this still holds true. I know it varies, but was looking for a general range. Thanks!

[@TheRabidfan]

Dude your beard and your videos are on point.

[@phillipromero7474]

Excellent information!

[@Ghostsamuari25]

Good morning. Thanks for the detailed vid. I would like to know what camera app did you use to show the heat on the cat?

[@spelunkerd]

With platinum being so expensive, is there a market for recycling the platinum from old cats?

[@don-cw1yz]

Yes,you see them piled up at junkyards,and they get picked up.

[@Cyclephoenix]

As an automated feature built into the ECM as In my 2010 Forrester The cruise control light will blink when a 420 code check engine light comes on as the dealer instructed me, " It's a safety feature!" Coincidentally my TCS light, also came on with the CEL and blinking cruise light as, you guess it, "a saftey feature!". thus 3 lights in all will go on for one simple 420 code. This TCS may play havoc with the ABS, they seem to be the sides of a coin, one forward, one backward. game of crazy dominoes. But once the 420 code is cleared seems the others fall in line.

[@jimmyfavereau]

thanks Brian : ) God Bless

[@PhilBourgeois]

Best vid on this subject!

[@briansmobile1]

+Phil Bourgeois Thanks Phil!

[@tuffbarber842]

+briansmobile1 educational video, videos like this help us understand how things work,why they break down thnks.

[@NN-gy7xl]

intro always turns my room into a big EDM dance party

[@dinamik967]

Hi, what kind of car tester do you use? Is it special Sybaru gear? Thanks BTW, you didn't install heat shields back on new cat. It is a big issue.

[@RodrinBird]

My ‘01 Forester has this same P0420 code and so do a lot of other ppl in the forum.. Is it actually safe running without the 2nd Cat? I might just do a 2nd Cat delete.. Will the code still show if there’s no Cat? I’m actually amazed at the construction of a Catalytic converter.. Thanks for the video Brian!

[@josephtucci3666]

Very cool vid. my friend!

[@venomx4093]

How are you liking your Maxidas diagnostic scanner? I've been wanting one for its bi-directional features and price.

[@SoundGuyDavo]

Brian, what was the brand of the complete part you chose? I need to replace a cat that is blown out at the seams and looking for a reasonable complete bolt in replacement.

[@scott2608]

Thanks great info, I always wondered what a melted cat look like.

[@aman.aman.7991]

excellent video great job

[@hoarybat61]

Thanks brian. at 8:41 it looked and sounded eerily like a Big Foot might cross in front of your vehicle. Darn no luck this time...

[@kartguy]

Mines plugged in my 2008 doing it tomorrow!

[@darylm.stephens9603]

Very informative thank you

[@ambertheater]

I love golden features!