P0420 Code. How to fix it. Don't spent spend tons of $$$.

P0420 Code. How to fix it. Don't spent tons of $$$. ~This also true for the po430 Code!
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[@FixingWithPassion]

Rare Occasions the O2's and Catalytic Converter's Go bad...VERY RARE. I have found starting with small things like, Gaskets, Air leaks, make sure something has not come loose, etc...usually has a better out come than spending $ 100.00's of dollars on Catalytic Converter's ETC. Take it one step at a time.

[@thomasmarquez6790]

As a auto tech 80% of the time it is a converter.

[@fury3600]

very often.... very often. hit a bump, shit breaks. gut the bitch, do the antifouler trick, never gotta deal with that shit again. this may fix it for a while until the p0420 pops up again, it takes a long ass time for it to show up again as the evap system is the last one to go through clearance. but i guess people like hearing false hopes than the hard truth, which isn't for the weak-hearted

[@khemicalgoddess4614]

May i ask what may be loose so i can check off the possibilities..thanks much great vid

[@chrisdeforce1]

Nathan Rohrbough can you leave links to the required parts

[@deanshoemaker5618]

@@fury3600 spray starting fluid on the vacuum line's or anywhere it could leak be careful but if there is a leak the motor will rev from the starting fluid

[@riverviewvineyard1143]

Check the easy stuff first, I just solved my P0420 found a vacuum line off. Got to get lucky once in a while.

[@FixingWithPassion]

Lucky you!

[@riverviewvineyard1143]

@@FixingWithPassion Your doing the public a great service, keep up the good work. All the do it your selfers out there appreciate your input. Truely

[@davidweum9334]

Good for you. What unit did you use. I'm looking at buying an Auto...somethig for $124.00 on sale.

[@szzpawnkntrl2018]

Thank you so much for the time you invested! You saved more than just my day😅

[@randomrebuilds]

Great piece of advice. My friend has a 3.8 Firebird with 50k and she has that code, however the car only has 50k on it, so I will relay the info over about the gaskets or vacuum lines.

[@warriorspirit9113]

Your a life saver man. You Thanks for the post

[@The_R-n-I_Guy]

Exhaust leaks can also cause a oxygen sensor/catalytic converter code. And usually if you let it go too long you will have to change the sensors after you fix the exhaust leak. Because your engine will run rich and flood the oxygen sensors and foul them out

[@FixingWithPassion]

Yea....not good

[@shadowman1992]

Need advice help please. Code p0420 car is not burning oil and is running fine obd2 scanner also says poor connection sensor 2 and pcmm could the issue be my down stream 02 sensor ?

[@christophersmithey1490]

Awesome! Got a PO420 code and ran across your video after about 6 others who never mentioned a loose line. Checked under the hood...cracked hose. Thank you!

[@jonmo2694]

What hose?

[@zcustomcarnesi]

Really good 👍 video . Thanks for taking the time.

[@carlosmunoz7934]

You are so right ! I had the code and it cost me nothing 13 dollars for a gasket , just like you said ! Thanks

[@FixingWithPassion]

Nice.!

[@iamlazarow3526]

Which gasket?

[@nofortunatesonII]

My 1999 Ford Ranger 3.0L 5 speed manual 2WD had the PO420 code. I replaced the pre-cat O2 sensor (passenger side) and the check engine light has been out for 5 years and still good. I purchased an OEM sensor (made by Bosch).

[@myyoutubechannel3161]

thank you Nathan i will try this! You're the best!

[@americanpatriot6038]

Your 100 % right ,not knowing i was younger had that code autozone guy said its o2 sensors i have 4 100000 miles ill replace all 60 dollars each code came back in 24 hours ,had a mechanic friend tell me look for a vacuum leak i did 3dollars fixed problem rubber vacuum line laying on hot engine melted hole .now i tackle everything differently. GOOD JOB.

[@frankbarker1568]

Check for vacuum leaks

[@glasser2819]

salesmen are rarely good advisers 😉

[@nordicpride9708]

Good video. From experience its my opinion that most DIY mechanics need to invest in higher quality scan tools. If you drive an older car and or work on a lot of OBD-2 equipped vehicles the simple code readers are next to worthless for diagnosis. They simply give you a code. I use X-tool but Autel, Topdon and countless others make dealer grade scanners that will simplify your diagnosis process.

[@shaunsmith9526]

Both my cars had P0420s hit at the same time. Did the full diagnostics. Ended up replacing the Cat in my Tacoma and as of 1 month later, no more P0420. I checked and replaced the intake gaskets with no success. On my Grand Caravan it turned out to be a bad gasket in my air intake plenum ($16 gasket). Don't discount a bad cat - it does happen.

[@FixingWithPassion]

Yea more that often ;(

[@irinakoran5233]

Thanks. Great video and info.😉

[@joshh9003]

I can’t thank you enough for the explaining I have a 05 Buick lesabre with the 3.8l v6 with the plastic plenum and there’s antifreeze leaks around it so that’s proly y my code is coming up I’ve changed the 02 sensor spark plugs and wires and ICM and all 3 coil packs and that dang code still came up so now I’m gona fix the gaskets before I tackle the Catylic converter!!

[@jbraun0ekrep]

Thanks Nathan. Great run through and information. Got PO430 on 2015 Infinity Q70. Qoute from dealer $4,200. Rediculous!!! Will be checking for leaks. God bless.

[@FixingWithPassion]

O MAN!

[@prestonworden9811]

Try Cataclean or something like that you’re car is rather new

[@toucan221]

looking at this in Feb 2021 never seen that before !! plastic intake, well one thing for sure, something new I've learned today. thank you Nathan

[@canyon.county208]

Lmao must not have seen many engines, alot of cars come with plastic intakes stock. My stock intake manifold on my 96 gmc is plastic

[@valdesadam]

I have 2 vans with this style of gaskets. They are easy to fix but they have a lot to take off. I dont want to do the work again! I just got one done and the second van started to act up. Lol Thank you for the video.

[@ralphwood5114]

Good information.I recently replaced the engine with with a Japanese import engine on my 06 Altima. The engine came with a plastic intake manifold. The original. Was aluminum. I have no idea why the aluminum one has shutter valves opened by a vacuum motor and the plastic one has none. I went with the aluminum. The engine runs fine now but had so much soft carbon in the intake it was causing misfire which I was blaming on on something I did wrong. I think it just needed some normal driving.

[@FixingWithPassion]

O yea? Hummmm

[@markmarkin8478]

I subscribed, awesome video! Thanks

[@sherilpowell3228]

Thank you so much

[@Yahs-our-El]

Thanks for sharing your experience and knowledge

[@FixingWithPassion]

My pleasure

[@alemaywkidane7659]

Good job explaining well thank you

[@tyronewalker5764]

Thank you so very much. 😎

[@W3BZSL1NG3R]

When you use a digital temperature gun. A BAD catalytic converter will be hot going into catalytic converter & cooler coming out. A GOOD catalytic converter Will be hot on inlet & even hotter on the outlet. Hope this helps

[@FixingWithPassion]

Yes thanks!

[@W3BZSL1NG3R]

TVWXMAN32 Np Did you ever put the gaskets on? I had a, 2000 4.6L towncar And had to replace plastic intake and gaskets @120k I Bought the 1 owner car for $3k With 70k miles. Sold it with 390k miles For $2.5k last summer and she's still rolling. Changed oil every 2500-3000 miles And beat it everyday lol 120mph governor :-p. Cya, W3BZ

[@FixingWithPassion]

Yea I did, I have done 6 since then...lol

[@W3BZSL1NG3R]

TVWXMAN32 I ask, Cause you said you'd post a link In description Of a vid update. K keep up the great work on you're channel. Well cya, W3BZ

[@jrblaxxx2340]

Yep you're very right

[@roscothefirst4712]

This video saved me a significant amount of money, been trying to solve this P0420 code on my 2009 Ford Flex- tightening the manifold bolts and checking vacuum hoses solved the code issue.

[@ThatBoyMichael1]

How did you use to check for vacuum hoses?

[@msntung]

@@ThatBoyMichael1 probably with water and soap

[@shawnt1206]

@@ThatBoyMichael1 - You can use smoke also to find vacuum leak.

[@Bowhunter-ft8cn]

Thanks for this. I just replaced my intake manifold gaskets and got this code shortly after. It was a new code so I was thinking something else went bad or I broke a connector on the O2 sensor or something. After you stated a vacuum leak can cause the p0420 code I went back and checked everything and found I left the vacuum line from my throttle body disconnected. Put it back in place and the code hasn't come back so far. Thanks for the information you provided.

[@leetos.4915]

I feel it's also my manifold gasket on my hybrid and checked with my mechanic and said it cost about $500 to do the labor...how many mileage do you have on your car? I'm at 240K mileage at my 2017 Hyundai due to Ubering full time

[@RamxRamx-fw3gm]

That is awesome information! Hope my Honda Pilot gets fixed by doing this. Thank you.

[@FixingWithPassion]

Sweet!

[@1redrubberball]

My 2003 Chevy Trailblazer with 217,500 miles on it, turned on the "check engine soon" light, with the P0420 code. In my case, a new air filter and a can of Seafoam in a fresh tank of 89 octane Shell midgrade (no alcohol), did the trick. The light didn't go out on its own, so I cleared it and drove 106 miles today. It remains off. Tomorrow I'll get it inspected. I did a lot of research and anything that can upset the fuel/air ratio, can cause that code! Check the simple stuff first! Good luck!

[@iamlazarow3526]

Has the light remained off?

[@1redrubberball]

@@iamlazarow3526 It remained off for at least 6-9 months.

[@leoguy1609]

If it's your Catalytic Converter you can often reset it long enough to pass inspection, was able to do that for nearly two years. Finally had to change it when emissions would complete a cycle. Mines was factory original from 2004.

[@FixingWithPassion]

Yea but....Emissions testing places are on to that. Until the vehicle/system clears so may start cycles, your not really passed and any emissions. Only after all start cycles are completed and the computer see this and is happy. There probes /computers will see that. Been there done that.

[@oljames1687]

..those engineers who designed the plastic intakes ought to be horse whipped. Like Dana Carvey said once- "..useless piece of plastic." ...!!

[@EGGINFOOLS]

This one wasn't plastic

[@dualsportdiary1150]

Just like plastic radiator tanks... WTF CHUCK????

[@RockyRepairs]

Engineer: let’s use metal Boss: you know how expensive that is? Just use plastic! We can’t lose this contract. Well blame the cracks on improper maintenance or something like that

[@phyllisbarnett6329]

Thank you so much. Saved me so much. 😥

[@TheGeno2001h]

Thank you man

[@chrisduhaime5689]

The propane test around the intake. Or break cleaner . Light spray around intake and vac lines .change in sound and speed your getting close.

[@chrisshackelford4385]

Awesome video!

[@nigeljohn6676]

Thanks brother

[@angelhoyle9376]

I have an 06 Ford Escape, my check engine light came on a week ago. took it to nearest auto zone and the PO420 code came up(that’s the only code), I’ve taken it to 3 mechanics and they all say it’s fine to drive but the whole catalyst converter needs replaced. now my Ford Escape has 3 converters on it fml so if I don’t have to have them changed that’d be great. However my question is will these seals and alittle extra air getting through cause my vehicle to sometimes have trouble starting and terrible gas mileage?? Or is one of my converters actually bad??

[@newguy1459]

I can't wait until you come out with the new video in step by step and in detail of how to solve this problem. I need to fix my p0420 problem.

[@escarsegat]

well you need to listen to the video

[@escarsegat]

spray water replase gaskets whats so hard about that you a man figure it out boy get off your ass

[@MrFlargas]

@@escarsegat You're an idiot

[@Kevin-wy8kc]

took the words right out of my text nut butterson

[@ddroppa101]

@@escarsegat 😂😂😂

[@dennyhao4027]

My old volo xc60 runed 130k miles and used no.87 gas for it.recently it appear engine check mark and went auto shop paid $200, recommended to change 4 oxygen sensors and cab. total amount will be $5000 more. And talked with the shop owner and found some useful info. ---use cabcleaners for 3bottles running 1200miles. The engine light gone. 😅

[@FixingWithPassion]

Nice!!

[@ryanchacon2005]

thanks for this man, i was worried until i found oil leak from driver side head cover creating oil burning smell and throwing this code

[@almirlimaj4354]

I have a 2012 Honda Accrod 4cyl. I got the same code, so I have replaced both O2 sensors and a Catalytic Converter, but the code is still there. I'll need to check for leaks now. Great video. Thanks!

[@abe5316]

What did you find after..?Thanks.I think lot of Hondas and royota have that code and toyoto and Honda need to help recall those product but people need to revolt against those two companies.it costing people lot of money but no one is talking

[@iBeTheRealWill]

@@abe5316 I Have A 03 Honda Deleted My Cats And Its Still There

[@selahveee]

did that fix it?

[@gibson7654]

Hello. I'm getting the P0139 and P0137 codes. I have also noticed that there is no voltage coming from B1S2 at all. Is it safe to assume the sensor is bad?

[@kingzionmusic]

I had this code the other day 98 2Dr Tahoe I put Royal purple in 3 tanks on 10 gallons each time the first 2 tanks the gunk caused the 0420 code and random misfire and burning 🔥 rich I knew it’s was because I was cleaning it 3rd tank I hit freeway within 10-15 mile Mark on freeway check engine light 💡 went off and it ran like a dream.

[@Supesfan88]

Hey there, old video, but! I've had a P0420 code on my GD car for a year. I've replaced the up/downstream O2 sensors, fuel pump, Valve cover gasket, etc. After replacing the VC gasket and fuel pump the light went off for a glorious 2 weeks. Came back on today - P0420 code again...gonna look into this manifold gasket next. I really don't want to put a CC in a 10 year old car with nearly 300k km on it. No matter how much I love it (I call him Speedy Gonsales - 2010 Chevy Aveo :))

[@alancameron2433]

Did you get the P0420 code cleared?

[@Supesfan88]

@@alancameron2433 Nope. but DEFINETLY the exhaust manifold (w cat). I'm going to use my multimetre on the o2 sensor attached to the manifold to see if it's faulty as well (or useable when I replace the manifold because O2 = expensive, dammit!

[@alancameron2433]

@@Supesfan88 I have watched some very interesting You Tube videos regarding code P0420.The more you watch the more easy it will be to diagnose correctly.

[@victorricocastro6940]

Wow man thank you

[@robertsimpson4984]

I solved the problem with some silicone grease ( from the pool store) on the Gas Cap “O” ring ! A 50¢ fix !

[@robertsimpson4984]

Now time to buy a new gas cap “O” ring for $8 or a new cap and “O” ring for $35. I’ve had it come back on 3x and it went away when I put the silicone on. It ALWAYS GIVES ME A 420 code if I don’t put 7 clicks in the gas cap when putting the cap back on !

[@NewLevelAuto]

I'm afraid you must be mistaken . A catalytic converter has nothing at all to do with your gas cap . Two different systems altogether. The evaporative emission system is responsible for storing and purging fuel vapors and will set codes like p0441 p0442 p0446 etc. But will Never set p0420

[@robertsimpson4984]

New Level Auto thats what I thought too... but I found a small note like this on my search on Utube and thought I would try it ... it worked!! And since then if it comes back on I just go give my gas cap 7 clicks and reset my codes and it goes away ! STRANGE but TRUE !

[@adrianapollyon5087]

He had a p0440 code. Not a p0420

[@smid2550]

@@NewLevelAuto right - it should have been a fuel system leak.

[@FixingWithPassion]

Update to this video: After fixing the intake gaskets the p0420 never came back on (perhaps rare on this fix and a 2nd 4.6 ). Perhaps air mixed with antifreeze tripped the code... a bit strange tho. If this is not caught soon, it will burn up the cats!! But if all else is ok, fuel trims, no other codes etc, leaks then cats probably are bad. It does happen sometimes. Tap on the cats to see if you hear rattling, if so they may be falling apart inside. Scope them and watch graph to verify. Happy fixing!

[@joseguzman5807]

I have this code on my truck, but I don’t know why the check engine light turns on and of every week

[@leetos.4915]

If you hear rattling while tapping the cat underneath, is that a solid indication to replace the cat asap?

[@JB91710]

If you get codes like that after your battery has died or been changed, run a vehicle specific Drive Cycle. That will allow your computer to get in sync with the sensors.

[@andrewflores4981]

Bought a $20 micro mechanic from Walmart. Used the torque app to clear the code whenever I get it. Comes on every now and then but not a big deal. Everything’s good as far as I can tell.

[@FixingWithPassion]

Make sure the bearing wax seal is still good. They fail.

[@ELI-vm9yf]

Such a good video!!!!!!!

[@testtester9539]

Solution starts at 3:25

[@soniarican6275]

Mine ended up being the Catalytic Converter 🤦🏽‍♀️ So NOT Cheap ! I ended up buying it of course cuz I had to and sure enough the Code P0420 went away 👏🏽😊

[@FixingWithPassion]

O my~!

[@lstruggy]

One day my 07 Cherokee check engine light started flashing. I was not even midway home from LA to Vegas. I did notice misfire when this light came on power loss was very noticeable as well as some shaking when shifting gears from park to reverse 😨 So i stopped nearest O’Reily n purchased new gas cap thought it would work nope. Eventually got home w light flashing periodically. Next day went to my mechanic and did a tune up replaced all spark plugs and cleaned the intake air sensor as well & found out one of the spark plugs was cracked 😳 That was couple of years ago. Check engine light never came back on not even once after I replaced all spark plugs. Now 2 months ago my check engine light came on w p0420 code below threshold w the catalytic converter. Last week I finally replaced my whole catalytic converter system because bank 1 cc wasn’t “reaching the right heat enter and exit temperature tested via infrared gun from my mechanic. So a new cc system was needed sigh 😔 costed me $1100 for the system from O’Reilly & also picked up 4 new Bosch sensors @$35 each sigh 😔 then went to Meineke and had everything installed for $300 sigh again 😔 I also replaced a cracked radiator a week prior to this $600 😔 now I’m gonna be eating cup o noodles for the next 3 months 🥺 I’m $2K lighter and the positive thing is my 12 yrs old Jeep Grand Cherokee Laredo is running like a champ again! Still cheaper than buying a new car. Hoping my Jeep (170K) would last until 300K- 400K miles 🤞🏽 Meineke ended up using the torch as well to take out all of my sensors because they were all rusted and seized they couldn’t take off the 02 sensors and the 8 bolts that connects the CC to the headers but they did took em 4hrs to finish the work but I only paid $300 and Meineke did an awesome job! 👏🏽 Moral of the story is this. I should’ve stopped the car right away when my check engine light started flashing couple years ago from that road trip coming home from LA to Vegas sigh 😔 but u know what? I had no idea that u we’re suppose to stop the car right then and there 🤷🏽‍♂️ I guess call a flat bed tow and have them tow my Jeep from Palmdale to Vegas which probably would’ve costed me close to $2K as well idk 🧐 I’m not a mechanic nobody told me about this, a hefty 2K lesson yaal. Turns out I damaged my bank 1 catalytic converter from gasoline entering the CC and driving it home for 2+ hrs flashing periodically. 😫 But she’s running good now sorry for the long ass rant yaal I hope somebody reads this and learn something from it ✌🏽anybody got $20 I can borrow? 🤑 👩🏽‍🔧 🚐💨💨💨

[@lstruggy]

Rusty Highlander 😭😭😭 she’s running solid right now 171K hoping to get to 300K or might have to trade her in a few years for something w less mileage

[@mrlatnemis1849]

Damn I can’t believe I read your ENTIRE POST!! Lol. Good shit!

[@lstruggy]

@@mrlatnemis1849 Tnx for reading it man 🤙🏽 I know that was like a long ass novel lol 😂 any how my jgc laredo atm just hit 199K and just started using a full synthetic Mobil1 oil. Also I just ordered a complete set f & r of cross drilled rotor brake set and ceramic brake pads from Amazon for $290 from Detroit Company Brakes because they are warped and worn out, my mechanic will install everything for $200 then nxt month I have to change my front oil pan and gasket because she’s slowly leaking and have been for the last 8 month just started leaking slowly all over the front frame recently I noticed some leaking on the ground as well so in a few weeks that’s up next then I’m done again for a while I hope 🤞🏽 lol. You know what they say about J.E.E.P. it means just empty everything from pockets 🤪

[@SleeplessinOC]

I am about to ask people to lend me money too , I’ve dumped so much money into fixing my 08 Yaris and I just got a p0420 code today 😭😖

[@lstruggy]

@@SleeplessinOC u got this bro! 🤙🏽

[@Victorsanchez-zk9mq]

The car is smoking that good shit

[@oldsmobileaurora7418]

How big of a deal is the extra air going into the intake manifold? Because I just replaced my 4.6 2v with a aftermarket dormant intake and the code came on after driving a few hundred miles.

[@dexscreenerbets]

thank you 🤘🏾

[@kidnplay2148]

I have a Chrysler 200 2015 and I got this code I’m scared to take it back to the dealership to fix it because every time I take my car to them to fix a problem they fix the problem then the check engine light comes on with a whole different code I waisted a lot of money just for them to fix one problem and then make another 🤦🏾‍♀️🤦🏾‍♀️☹️

[@julied915]

That's it! I'm goin to mechanic school. Not to be one. But to know how to fix my own car😃

[@FixingWithPassion]

Ha ha...lol

[@christianbartholemue5480]

Go for it girl! You're gorgeous too by the way!

[@historyhunter5215]

Nathan, this Nathan says Thank You!!!!!

[@ripptydevibes2581]

I completely disagree! Doing this full time for 15yrs as a shop owner, a simple "live data-fuel trim" check will immediately expose an "air/vacuum leak" and MOST of the time this is going to trip a lean code. With your insistance of lean issues you dont even provide us with a fuel trims check?? Thats like taking a misfire code P0301 and saying its usually always an air filter.

[@smellurfingerrcdejesus9176]

my hero

[@Meleeman011]

best diagnostic tool is your ears. hands down. I saw p0420 and i replaced my gaskets on a toyota sienna, and it ran much better when i replaced intake and throttle body gaskets, although it runs a bit rough on high way speeds which doesn't make sense since the rpms are lower than when getting upto speed. my guess is worn suspension parts, but they are certainly still good. the last thing i know is a problem is probably oil in the cat, since it has been running rich and blowing blue smoke before i replace 02 sensor.

[@FixingWithPassion]

Nice!

[@dominiquelewis1871]

i just changed my temp sensor gauge and that code came up, do you think may not be tight enough or did something else go wrong?

[@Perrin2401]

Same... I’m not sure what happned

[@JesusMunoz-dw9ms]

I love the angry face. But the video is also helpful.

[@FixingWithPassion]

Nice!!

[@media333]

My 99 Chevy Suburban service engine light comes on just once in a while. In the past, I cleared it to see if it would go on again. Guessing it's been a year that it's been off, (anyway, it's been a long time,) now it's on again. If I have a major problem, wouldn't the light come right back on after it's been cleared? (P0420 Catalyst System Effidiency Below Threshold Bank 1)Thanks!

[@downside1237]

I have a P0420 on my 2011 Honda CRV I changed both oxygen sensors and it went away for about a week and then it came back so I'm supposing I may have a leak somewhere. I checked under the car I didn't find any holes anywhere but I did notice that the top or pre cat catalytic converter is very red and bluish does that indicate damage? If it does do you suppose that I could be burning some fuel or oil into the catalytic converter? I don't want to replace it without being sure that I found the problem that caused the damage to the cat. what would you recommend on how to proceed?

[@MustangGuy1996]

My 2011 mustang 3.7 has p0420 was causing power loss and misfire but only when DECELERATING. When accelerating only slight power loss, no misfire. I replaced the bank 1 o2 sensor and catalytic converter (when i removed the old cat it was full of broken pieces inside.) the code hasn’t come back yet but the symptoms are still the same with the replacement making seemingly no difference. Just did my plugs 6k miles ago too..do you think it’s reasonable to conclude if the cat was blown on one side that the other side is likely the same?

[@uawsux]

If you want to check if you have a vacuum leak take a propane cylinder with the engine running a long hose on the nozzle and shoot propane out of your little tank you're settling tank soldering tank down along the edges of the intake manifold around your Christmas trees around your diverter valves around your bank vacuum switches and if your idle goes up if your idle goes up that is where the leak is

[@FixingWithPassion]

Good tip ;)

[@tysenhansen514]

Thank you so much for the guidance. The last thing I want to do is take my wife's car to the mechanic for this code...

[@bryanlopez1061]

Lol same

[@nikovandh]

My freeze frame always shows perfect fuel trim numbers very close to 0. I think I have symptoms of a possible very mild/slow intake manifold coolant leak though, which from what I've read can get burned in combustion. Do you think this, rather than vacuum, could trigger my p0420? No other symptoms or codes. Car runs perfect.

[@496elcamino2]

After I changed the plastic intake 2004 lesabre I got this code. I’ll check for a leak. Hope it’s it, thanks, great video and help.

[@FixingWithPassion]

ok

[@jeffk3776]

If you get this code on a 1.6L Kia Soul, take it to the dealer to execute the latest recall. They will reprogram the ECM, and will probably replace the catalytic converter.

[@calvillocobra98]

I got a 2014 kia forte 1.8 just replace the converters and the cam shaft sensor and the crank sensor and the stupid light keeps on coming back

[@Ginnito]

@@calvillocobra98 what have you done ? Am having the same problem

[@calvillocobra98]

@@Ginnito never fix it sold the car

[@Ginnito]

@@calvillocobra98 guess that’s my next step ! Thank you 🙏🏽

[@calvillocobra98]

@@Ginnito no problem man i think the problem was oil sludge

[@richard3769]

Thank you for this video and advice. I also have the same fault code on my car and other symptoms surgesting a vacuum leak.

[@FixingWithPassion]

Nice!~

[@zacharyward3123]

I get a “test value” of .257 with a minimum requirement of .500 with my P0420 bank 1 code. I have new cats. Does that mean bank 1 pressure coming out the exhaust manifold is low? Can Intake be causing that as well?

[@ralphwood5114]

I got lucky with the 420 code. The Japanese import engine that I put in my 2006 Altima had a serious engine misfire code because of so much soft carbon in the intake. I put a couple of cans of Sea Foam in a full tank of gas. That solved the misfire problem but caused a 420 code. I removed the primary oxygen senser and sprayed a whole can of Berryman Carb cleaner.The 420 went away. Bought the car with 225 k. After a couple days I realized I had been took. Ran good but needed valve seals. When I started changing the valve seals I realized the valve guides were worn. What the he'll I ordered a Japonese import engine from NJ. Good engine but probably has never been driven over. 30 miles per hour. Beautiful car. I guess it's better than buying a new one.

[@FixingWithPassion]

Nice!

[@kellyokamoto1604]

I have that EXACT Expy-same year, engine, etc. Even same color! I had that P0420 code about a year ago, reset it, and it never came back-YET. I DO have the "Evap Sys" test not complete. I've been trying to trace that problem for a while and can't seem to find the leak. Had a shop smoke test it and they said it "could" be on top of the gas tank, they'd have to drop it, and it'd cost a minimum of $700.

[@markchidester6239]

Go somewhere else

[@leordo11]

If you have un metered air or air leak the computer will set a code p0171 or p0172 system to lean look at your fuel trims then you will know for shure.

[@lloydstowell4302]

I have I have a Subaru with 02 sensors do I need to change them all or just the last one?

[@Bwanar1]

Hey Nathan, thanks for the video. Where you able to actually detect the leak on the intakes before ordering and replacing the gaskets, or was this just the easiest/cheapest place to start? And if so, how? Thanks in Advance!

[@salr1473]

Old trick to find leaks is to use a shop vac to blow air into the tailpipe. Use a soapy water solution which will create bubbles where air is escaping

[@adamjoseph1970]

Nice video! Went to mechanic, they said my cat was fine but needed both of my 02 sensors replaced(which I did, both oem). However, I still get the codes! I have a 2013 Corolla S. I don't know for certain if the intake is plastic or not but I'll surely check asap! I also have a very small evap leak(p0456) but im not sure if that has any bearing on the p0420 code. Question is: Can the gaskets leak if the intake is NOT plastic?

[@FixingWithPassion]

Adam Joseph .....yes...my expedition is an aluminum intake and I've had to replace gaskets on them and for other people.

[@jonmo2694]

Use gumout or catyclean

[@olid.7568]

Great video 👍👍

[@ricardorodriguez-se7tp]

Hi I have a 2012 F250 6.2 P0420 when I turn off the engine I can hear a quick hissing on the manifold its plastic do you think it might be the problem Thanks

[@cooterpolluter]

Recently changed my intake hose because it was cracked. Likely have another leak. I will check.

[@brandenjohnson2980]

What kind gaskets do I need to order for the 09 traverse wat would I type to search to buy for code p420

[@aaronm406]

Yup, my ‘05 1.8 vibe has P0420 and driving me crazy to get rid of it.

[@f4tc0w]

You would have a p0171 if you had a vacuum leak. PO420 usually means bad catalytic converter. You can monitor the voltage of the downstream sensor and if it fluctuates with the upstream sensor you have a bad cat

[@northernswedenstories1028]

Came here to say this. I think this guy has it all wrong diagnostically. P0420 is almost always the cat that is bad if there are no other codes. If I also had a lean or rich code then I would suspect air leak or fuel delivery. But p0420 on its own is a clear indictor to suspect the cat. Confirm by testing pre cat and post cat o2 sensors for mirrored air flow patterns.

[@TheNYgolfer]

Well put. Thanks. My downstream sensor stayed pretty steady at about 0.8 V. The upstream sensor did not fluctuate much and stayed around 0.5 V. Besides the P0420 code I also got a P0133 code. Upstream sensor slow to respond. Going to replace upstream O2 sensor.

[@iamericotoo]

Heyaaaa I have the code showing on my Elantra sport and it’s beginning to reduce engine speed at high RPMs. What do you suggest I do.

[@danielcordova6356]

My 2001 Toyota Corolla has po420 but I don't know what it is any idea

[@todaysupdate6824]

Hi, my check engine light on today . It say catalytic converter defect . But I have change it one month ago . Anyway I erase the code and check engine light gone . So my question is will it come back again. If so how long it will take to come back. Thanks Golf 5 ( 2008 ) 1.4 patrol engine I drove with bad kat about a week but no engine light on and after I drove another week without Kat no engine light on . When I change my both Kat and drove 500km not engine light. Then I put fuel injector cleaner and drove another 150 km . And after engine light on and it says on my obd2 Kat defect.

[@mikecrane6096]

The smog narcs in Kaliforniastan check your O2 sensors to bust you for using sensor extenders.

[@FixingWithPassion]

Word!

[@eduardogarcia7228]

Great content but was expecting you to perform a smoke test to show if in fact there was/is a vacuum leak to confirm your original diagnosis.

[@FixingWithPassion]

I'll do that next time...;)

[@87studga]

I have a 2007 Mitsubishi eclipse and my exhaust flange isn’t tight and I did the water and soap test with the vacuum and my exhaust flange was bubbles could it throw the code p0421 and p0431? Please help. I change all my o2 sensors as well

[@rzjk301]

There are youtube videos on how to make a smoke machine out of paint cans. This will help you test for leaks in your intake and evap system.

[@FixingWithPassion]

Nice. Thanks!

[@keithupton86ku]

A can of brake parts cleaner is like $3 and does the same thing.

[@adrianapollyon5087]

@@keithupton86ku but it is invisible 💁‍♂️

[@keithupton86ku]

@@adrianapollyon5087 And? Guess what happens when you spray brake parts cleaner into your intake while the engine is running? It'll sputter and possibly die. The same thing happens when you spray brake parts cleaner into a vacuum line, or a leak in the systems(s).

[@volvoguy76]

Nice. I get an occasional 0420, and just got an 0420 and 0430 at the same time. I'd been logging data on my phone with Torque. Both cats and all 4 O2 sensors are working as they should. Time to go clean some grounds before considering replacing my plastic manifold. A gasket set is a third of the price of the manifold for my car.... and the manifold includes a full suite of gaskets.

[@halfmoon5022]

Would this be the cause of P0087 and P2279 stored and P0420 pending? All pumps have been swapped already

[@tyronewalker5764]

My 2000 Dodge dakota has this issue!

[@RS-nm8je]

Nice info but you should have talked about how big a job and how much it is to fix. I was looking more how to fix.

[@billsteil8002]

po 420 code first change spark plugs a misfire will cause to much unburned fuel into the catalitic converter and also distroy the converter.the injector cleaner will help clean the injectors and the converter.Also check for a bad coil check eachcylender for misfire.Unplug wire if motor shakes thats the one.

[@FixingWithPassion]

Word! But a lot of times...its to late the damage has all ready been done to the cats. But you are right. That's why is always good fix a issue right away before it causes a chain reaction sorts.

[@mrdrv999]

@@FixingWithPassion that's what happened to me. Poor maintenance caused 2 bad spark plugs, this caused 2 damaged ignition coils and finally the cat was destroyed. It's costing me a ton of money since I imported a GMC Terrain to Ecuador and there are no parts for replacement available in here.

[@TreDogOfficial]

Did you make a video of the gasket replacement and the subsequent engine light resolution?

[@FixingWithPassion]

Yes, PO420 was burnt up cats. PO430 was the intake gasket. Search for them on my channel. Thanks for Watching!