Thats one of the best Cat Vids ive viewed because at 90k my cat is starting that useless phase, even though it runs perfectly. The p0420 error code is constantly tripping the Engine light. Seems its best to change mine if I can get a good price for doing it. Thank you, you know your stuff, a real petrol head.
2010 chevy cobalt.... I've had a code for lean condition with downstream O2 sensor even after changing that sensor. I've had a smoke test done and also replaced my brake booster and fuel injector o-rings... Last resort is manifold gasket even though no leak detected.... My old cat was original at 214k miles... Replaced today.... Do you think that'll do it?? Thanks and God bless
Nice, helpful video. A question! What did you do to the massive leak underneath with all the bubbles? Did you change that part? Was it attatched to the catalyst converter you changed? // Thanks!
He should change it because my daughter had the same car with the flex pipe leaking exhaust fumes inside the car while she was driving. She started feeling tired while driving and until I got in her car, I could smell exhaust fumes while driving. I replaced it and all was good after that.
Hey Robert, did you use an OEM cat? I've had issues in the past with cetain brand cats not passing the test, even when brand new. Mike Becker, Senior Insturctor
Catalyst converter still looks good, before to spend money to get a new converter, I would soak the catalyst converter in lacquer thinner, then clean it out. It worked for me the last two times. carbon built up is mostly the reason why setting this code, clean it up it may work again.
Although there's no physical damage to the CAT and its not clogged, over time the rare earth metals in the CAT will be depleted to the point that the necessary chemical reactions to remove the toxic gases from the exhaust no longer take place. So it basically just wears out. And great tip on using shop vac to find exhaust leaks!
Great video! I have had people bring their vehicle to me because when their "check engine" light came on, they brought it to someone who claims to be a mechanic but i call them a bonafide "parts changer." They use their magical scan tool that says "P0420" and immediately tell the customer that they need a new cat. Then a few days later, that damn yellow light reappears, so they come to me or another mechanic. 90% of the time (after the cat has been changed), I use my smoke machine (but I like your method with the shop vac also) and I find an exhaust leak pre O2 sensor and repair it for a fraction of the price they paid for a new cat that was just a waste of money. These so-called mechanics should be made to give their customers a full refund because too many are ripping hard working people off and giving the good mechanics a bad reputation. I love to see good videos like yours that show scan tools are just to give you a good starting place to look for the problem and they aren't a "super tool" that tells you exactly what part is failing 100% of the time. Again, thanks for a truly educational video. Well done.
thanks to people like you . i had a mechanic charge me 700 dollars for a 03 Lexus IS300 MAF . Had nothing to do with the code i even took it in for. (my fault for not trusting my research telling me it is the APPS/TPS) . They gave my car back with the same TPS codes on there and siliconed my Throttle body connectors together so when i had it replaced for 1/3 of the price by a home mechanic-- he had to break the connectors and tape them back. I successfully sued in a small claims court. Thanks to this video i might save 1400 dollars as well.
Hi, i bought a premium exhaust and had local mechanic fit it, he did mention that the gasket provided with exhaust didnt fit correctly so he went and got another gasket, i cant help thinking the other gasket is the problem have problem now, i driven for about 3 weeks after fitted now car struggles on acceleration and and engine light came on, so i put my own reader on it, and im getting code p0420 and p0303, i wonder if code p0303 is triggered by p0420??? It just seems odd how the car was fine until i had the exhaust change, i also bought a 02 sensor but dont wanna change it if thats not the problem. I dont have a hoover that blows air how would i do the smoke 1? Thanks
Great advice for the smoke machine. I was thinking about using the same for my P0420 code on Toyota Yaris and bad fuel mileage. Smoke machine will do the job since I hear my exhaust is somewhere cracked. Mechanic said "oh, P0420, a new cat is needed, that's around 200eur just for the part". 😂
My God, man. I almost feel like you designed the system yourself. I have not ever heard anyone with as much grace in knowledge as you have explained in this here video, sir. Bravo!
From what I have read and viewed else where, use a scanner to monitor the live data for both of the O2 sensors. When the car is still cold, the output O2 sensor will mimic the input O2 sensor. Once car reaches the operating temp, the converter starts to do its job, and the output sensor will go to the steady line. You can also use a laser temperature gun to measure temp at both in and out pipes of the cat when at operating temp. If cat is working, i.e., burning the residual fuels, the output will be hotter than its input by quite a bit.
Well done Mike, You can only go by the data shown. Imagine if you just went on your gut feeling after looking at the cat substructure - it looked relatively OK & had no rattle. You would end up with an unhappy customer and a lot of wasted time. The data was clear & the diagnosis was spot on. Cheers MiracleMAX
Thank you so much for this video. Clearing my P0420 error code in Camry 2005 with 184K miles. I followed by blowing air in the rear muffler so it pushed all "restriction" on the catalytic converter. First you need to add CATACLEAN in your gas tank (follow direction, drive it per direction). Then I removed the upstream oxygen sensor, then adding blowing air in the rear muffler for 15 min with Shop Vac Exhaust trick. You need to close the opening on the oxygen sensor for 2 seconds, then open it so the air pressure will "push" the restriction. Do it as often you like during 10-15 min. Then install the oxygen sensor back. It make my check engine light disappear (error code P420), and passed NJ inspection for my Camry 2005 with 184K miles. Thank you, save my original catalytic converter, save money, as of now I already drove 150 miles without the check engine light.
Mike, I've found that "Mr. Bubble" is just not given enough credit in the auto repair industry. Great as you've shown, also great for exhaust pipe weld integrity check, AC leak check, and a poor man's fog machine! (Much faster than fogger).
I had to literally junk a 98 Camry xle at 138k miles because our local mechanics are totally incapable of basic diagnostics. Same code and already replaced the converter. V6 loaded model too. All these local clowns can do is parts cannon you. They all wanted to replace it again despite overwhelming evidence it was running way rich. The car could not pass inspection.
Hello, I just discovered your channel. I subscribed within the first 20 seconds. Seriously. Within the first few seconds, I noticed how well shot it is as well as the color grading and lighting. Great presenter right from the start. Nice one, Mike.
WOW you just may have saved me over 1000 dollars for a new cat! I have never been so excited to see bubbles out of my header before! Ordering exhaust gaskets now! Fingers crossed. THat trick with the shop vac really blew my mind, its so brilliantly simple! like most great ideas are.
5% just clog will trigger the code that guy or woman just needed to clean there cat with some lacquer thinner would of clean it and would of save money
Would like to thank you for creating this video. You saved me a trip to the shop and helped me find the leak (exhaust manifold). Thank you very much sir!!
have a problem with my camaro. All tests show that my cat is doing it's job but it keeps popping up po420 and 430 switching between the two. I will do this exhaust leak test tomorrow as I have already done a vacuum leak test on all my hoses and that didn't find a problem. but what I would like to see is a video if such a test exists how to do a test to see if there is a leak in the intake gaskets. It seems to be impossible on my v6 engine without taking off the intake. so how would someone get gas fuel to those gaskets without pulling the intake off?
It's nice to see the correct technical information. You can't set a 420 or 430 unless the sensor is switching with fuel trim. A leak causes a bias condition, as he noted.
What about the leak @ the flex pipe? Did you replace it with a universal weld in or did you get the ok to get a new direct fit with the whole assembly OEM wich includes flex and converter? Nice video👍
Nice job Mike I liked the shop vac and bubbles genius. Lots of 420 codes going around, nice to see sometimes even visual good looking cats aren’t efficient enough. Thanks for sharing
Impressive you did not break any bolts with over 300k miles. Good tips on locating the air pocket. It reminds me of the method plumbers and HVAC technicians use to find leaks in gas lines.
Hey, great explanation of the process! One question- did you check the emissions levels before changing the catalytic converter? Were they higher than usual? I have the same error on my car, but the emissions readout on the exhaust seem okay.
I liked the vacuum trick! 👍🏾 And I was thinking oh snap (literally) no broken bolts on this one? He lucked uppppppp‼️😂 But either way good job and very detailed and to the point video!
Great video. Can you share the catalytic converter you installed on this model? I have same - 2005 California model so it should be the same although the O2 sensor location is slightly different and the Denso is the only one that seems to match.
Take home lessons: Japanese cars and parts are excellent. You are a real pro mechanic and a great instructor. Well done !. The shop vac / soap test.....so simple, so effective !!
That is a great test ! I have a exhaust leak "tick" that has been driving me nuts. No codes , only when cold , smoke isn't a option. But I have a shop-vac and bought the wife a bottle of soap just the other day. Pure genius ! I thank you Sir !
Same I also have a tick at cold start usually isn’t very noticeable at operating temperature. P0420 code, I swear I think it’s the exhaust manifold gasket leaking…it’s a 2017 Ford Transit connect.
Excellent video. Really cool trick with the shop vac and soapy water. My 2002 tacoma 4x4 is throwing a P0420. Since it has 2 cats, I'm hoping it's either a sensor, or air/exhaust leak. Will test those before buying a whole new cat.
WOW, 330k!!! Sweet! Sadly it looks like there's nothing built today that will make that distance anymore without major engine work (timing chains, mostly it seems). If there is, it will be Toyota, for sure. That's a great exhaust leak finder - great idea! 😎 I've used my cheap paint-can smoker on exhausts several times. It does work, but it's harder to see where the smoke is coming from. Much easier to see bubbles. I just did a '06 Corolla cat, 137,6xx miles - the top of the cat had blown right out from rust. The rest of the system wasn't a whole lot better, either. Replaced everything from the cat back. A little different design on this one - I didn't have to touch the header. The cat was bolted to the header underneath. I also got both the flange nuts off after getting them cherry red, but the studs were destroyed. Had to feed a bolt in from the top, while balancing the assembly on a lift jack stand, and attempting to tighten with my left hand. The classic reach-around, lol. After a few choice words were shouted, I got it tight and leak free. 😁
Hey Smitty, crazy right? I agree, 300K plus may be a thing of the past. Ahh yes, the "choice words" the go-to tool in the mechanics tool box that always get's the job done. I keep mine in the drawer right next to the flying wrench and the kicked over oil drain bucket ;) Mike Becker, Senior Instructor
I think I found my problem I replaced both Catalytic converters in my 06 Camry XLE 2.4 with ceramic converters and now months later I get the P240 code and I think it's the ceramic converters. This car wants OEM parts.
That's completely waste...i mean changing exhaust manifold with cat. If it was ok just fix the leak and that's it! Owner have to much money? Spend on rust issue 😋 Anyway that's nothing shocking uncovered here
Thanks for watching Jacob. Not sure if you actually watched the video though? The exhaust leak could not cause the P0420 code on this car. Did you miss that part? Mike Becker, Senior Instructor
Hi .sir Thank you it is helpful video Iam from iraq and our gasoline is not good matter .can the bad fuel cause a code p0420 and i use for that a catalytic converter cleaner and the check engine light turn off
Hey Ghassan, thanks for watching! Sure, bad gas can cause a cat to go bad. Really anything running through the cat that isn't a good stoich mixture will cause it to fail eventually. Mike Becker, Senior Instructor
The way you show in video looks like the Leak come from the Joint..I’m not saying the Cat isn’t Bad.. But if it’s me I will try some Cleaner Product first…cheers..
So I have a 2003 Toyota Camry 2.4L I got this code. I put a new bank 1 sensor 2 O2 sensor on it OEM . Still got the code back I then put a new cat on it. Still got the code. I did not do the up stream sensor it looked to have been replaced. Also I just got this car. So I'm not sure I do know the up stream sensor is not original to the car. It cam out of the old cat with no heat at all so I'm guessing it has not been there to to long. Cold that be it or is there other things it could be ? AGEN new cat and new down stream 02 sensor. Still getting a p0420 code.
Hi Keith, What brand catalytic converter did you install? Many aftermarket brand catalytic converters do not have enough oxygen storage capacity and will continue to set a P0420 DTC ~Ryan Wilsing
Excellent video. Fellow Tech here and you nailed everything about the diagnostic and covered all the high points that people need to know to work on their own cars. Great job!
Just found your channel and subscribed. Did you repair the exhaust leak at the flex pipe? I wonder if that was causing the O2 sensor reading and if you had fixed that you might not need to change out the cat.
It seemed the cat responded to lean and to rich OK, but I didn't see how you forced it rich. Also, if the cat responds showing full rich and lean, doesn't that prove the cat is good? I must have missed something.
That test simply confirms the function of the sensor. An oxygen storage capacity test needs to be performed to judge the health of the cat. A switch rear 02 usually tells you enough though. ~Mike
Some mechanical is saying you cant ever replace one catalytic converter ti fix po420 warning. Hes saying i need all sensors and both cats replaced becuase they are all connected and the computer will still pop up the warning without replacing it all. What do you all think?
You only need to replace the components that have failed. While all the sensors and catalytic converters work together, they don't need to all be replaced at the same time. Ryan W Technical Instructor
I am located in Ny - can i purchase an aftermarket cat not approved to be sent to NY - to pickup in NJ and install it NJ - would my engine light will come on or I won’t pass the emisión inspection in NY?
Perfect timing. I'm stuck in a hotel with my Jeep in a Amarillo, Tx. auto repair shop for a large oil leak. What else to do but watch videos. I like your way of finding an exhaust leak. It was a great visual for RU-vid as well. Great fix too Mike.
So I have an 07 Corolla that I replaced the cat due to bad cat. After replacement I still get code and through your method of testing I was able to find a leak at header-head. The car is running extremely rich and was wondering if this leak is the culprit. It’s before my a/f sensor so was just wondering if the header being warped could cause the p0420 my only code and an extremely rich condition. All other gaskets have been maintained and there is no other leaks or codes
Hey James, thanks for watching! If you have a leak before the 02 sensor air will enter the exhaust and and cause the 02 sensor to read extra air causing the computer to add fuel-making it rich. So yes, this could definitely be the cause of your issue. ~Mike
Another way to tell if the cat is bad is by using a thermal camera or infrared thermometer to measure cat inlet and outlet temps. Cat outlet temps should be higher than inlet temp on a good cat. If inlet and outlet temps are the same, then it usually indicates the cat is bad.
Hey Frank, I have heard that teqnique as well. I used my FLIR C3 camera with the old and new cat. I was unable to see a temp difference. Maybe it was just the angle? I wasn't able to get a very good shot on the cat. Mike Becker, Senior Instructor
run time is a factor, cold star and check before proper heating is a factor, also is the engine running properly... bad sensors can throw off the heat cycle by computer staying in open loop or bad A/F ratio. which we all know can kill cat.converters as well as skew temperature readings by far
This is very educational video and well edited to the points. Thanks. Out of curiosity, maybe it's good idea to replace the catalyst converter for the vehicle. For the same situation with P0430 and leak, do you have to replace the converter? Or simply fix the leak? Thanks in advance.
Fix the leak, clear the codes and then drive it enough for the catalyst monitor to pass (I am assuming this is your personal car, So I would just wait and see if the light comes back on, and If it does check the codes again. If the same one comes back it could be an O2 sensor or the catalytic converter. While you're fixing the leak make sure the wires from the O2 sensor are in good condition. At that point you would need access to live data to distinguish between them. Catalytic converters are a repair that will often cost $1,000 or more. Before you replace one it's important to fix any engine issues first or you'll trash the replacement very quickly. (Days or weeks.)
So how long should it take to run a full cycle after dealing with a code like this? I bought an 06 honda crv and less than 24 hours later I got p0420 (a nightmare code I was trying to get away from with my Subaru) long story short the clowns at the dealership half-assed the installation of a new cat and sensors and packed some significant gaps with JB weld. I dropped the exhaust and properly welded their bubblegum tacs and cleared the code. Since then it hasn't come back yet but the I/M readiness still hasn't completed for the cat or the evap.
How would you hook up the shop vac on a dual muffler system? Would the vehicle still run with one side plugged? I guess I could try to find another shop vac and hook one up to each side. I have a P0430 bank 2 code. I know that’s the driver side code on my f-150 5.0 motor. I watched another video and they said you can take the temp before and after the cat. If the front temp is higher than the back; the cat is bad. Have you ever checked one this way. My vehicle read higher on the front on both sides; but I don’t have the P0420 code; at least not yet. My 5-8th cylinder began misfiring when this happened as well. Those are all on the drivers side as well.I changed the plugs and it runs a lot better; but still not normal. The truck only has 135k miles.
Hey Jesse, thanks for watching. The customer chose not to fix the rest of the exhaust. The goal for him was to get this vehicle through emissions for as cheap as possible. Mike Becker, Senior Instructor
Hi I have Camry 2005 and the same code is showed up. When I compared the voltage of your sensor to mine, I found that my sensor 1 bank1 is reading 3.3 and more. However the ox 2 bank 1 is more steady between 0.6 to 0.8. Does it means that my catalytic is working or what is the problem?!
Hello, If it is reading around .6-.8v at the rear sensor it would indicate that the catalytic converter is working. But the failure may be intermittent. Have you tried having someone drive the vehicle while you monitor the rear sensor? Some catalytic converters can work at idle and not keep up under any load. Thanks for reaching out! ~Ryan
@@GoTechTraining yes I did that and the RPM keep reaching between 0.6 to 0.8 but the front sensor is reach 4.6 to 6.4 is it normal ?! Also I smell gas in idle, so do you think if the manifold gasket is leaking will indicate to the same code of p0420?!
It's highly possible. This customer needs his car to get to work. Fortunately for him, the WI emissions test is good for 2 years. I highly doubt that car makes it past that. Mike Becker, Senior Instructor
I switched over to Shaeffer 5/30 and mine cut its oil consumption in half, from 1 quart in 3k miles to 1 quart in 6k miles. Gas milieage went from 33 to 37mpg. I bought the car used w 240k miles from a charity house with smog. I got my DMV tags then the check engine light came on with a P0240 code in 100 miles...so I know they fudged it. I got 2 years to fix it. Car runs great.
great video, just got a PO420 on my Ford Edge 2019, I doubt that the cat is broken at only 80k miles, rather plugged. Do you recommend to add some fuel additive before inspecting the cat?
Hey Buku2008, interesting that you are seeing that on such a new vehicle. Are you burning any oil or coolant on there? What engine do you have? I'm not a huge fan of additives, it's a band-air on the problem, in my opinion. ~Mike
@@GoTechTraining It's 2.0 ecoboost gasoline, it's definitely not burning any coolant, oil level was ok 2 weeks ago (checking it once a month). Sometimes I can smell something burnt coming out of the vent (like exhaust fumes). The exhaust system was checked in 2 different shops and there are apparently no leaks......interesting.
338,000 miles and didnt break any bolts = Toyota build quality + owner takes care of the car + your proper removal technique. Great vids, keep it up! Stay gold.
I like your "find the leak" test Mike. Maybe it was a California car that got moved to Wisconsin? Anyway, good fix. Like your new shop! WOW! Beats working in a house garage or worse, outdoors! Hope you're all well. Stay healthy.
Hey Mike, thanks! We see a ton of Cali emissions cars here...not sure why. Thanks, the new shop is nice...just need to get a ceiling in and some insulation work done. Got a VW to sell to fund it, haha! Mike Becker, Senior Instructor
I think across the United States there is a high demand for well used but still functioning automobiles. With greater income disparity lots of folks with lower paying jobs need any form of transportation that is somewhat reliable and will get them to and from a job and is in the $1000 -$3000 price range. That would mean a vehicle with 200,000+ miles and is 10 or more years old. Any car driven in the northern "rust belt" that fits that criteria will look like "Swiss cheese" (pun intended). But there are lots of these cars in the southern states and California where road salt induced rust is NOT an issue. You cannot get much trade-in value in their local domains but used car dealers can afford to pay a little to a southern state dealer for the vehicle and ship it north, sell it and make some profit.
@@juancamberosg.593 basically you can do it two ways take off the converter and soak it on laundry degreaser for 12 hours, or you could use a product! There are many on the market! Before put it it back on you need to make sure it is dry by the air.
Would you say that because the exhaust leak was behind or after the CAT that it was not the main problem. I didn't see the flex joint get replaced. Great analysis 👍. Enjoyed this video.
I have a 2014 Hyundai accent. My check engine light came on today with this code. It came on right after an oil change and replacing the oil drain plug gasket. The oil change guy must have done something right? My light has never come on before.
Hi Paul, Changing your engine oil shouldn't have an effect on catalyst performance. You could check your oil level, if your engine oil was grossly overfilled, it could cause your engine to burn oil. This is the only scenario I can think of than may cause a cat issue. ~Ryan Wilsing
Excellent Video Mike!! and Great Idea to simulate exhaust leaks. Two questions: Did you install OEM Cat and What OBDII Equipment were you using.....Thank you!
Hey Eduardo, thanks for watching! This vehicle was diagnosed using my Autel Elite. I installed a Direct Fit Cali Emissions aftermarket cat. Mike Becker, Senior Instructor
I am guessing you disconnected the vacuum cleaner from the tailpipe before starting the engine. Can you also perform this kind of test with a smoke machine leak detector???
Hello, Hahaha, definitely disconnected vacuum cleaner! A smoke machine works, but doesn't develop the high pressure like the vacuum cleaner does. ~Ryan
Listen everyone….. before anyone freaks out about the PO420 code, always check your O2 sensors, if your O2 sensors are bad it will trick the system of your car to make it think that it’s your Catalytic converter going bad. I had a PO420 code on my 2007 Chevy Malibu and i just replaced the sensors and boom CODE GONE!
Hey Mike, all that hot air that you have, you probably don't need the shop-vac, right? haha just messin' with you. Thanks for watching :) Mike Becker, Senior Instructor
Hey Yipchi, I suppose there is a slight risk of that. It would only happen on the cylinders with the exhaust valve open and it would have to be very small. Mike Becker, Senior Instructor
That's a tough question, I have personally has a lot of issues with aftermarket / universal catalytic converters. I think it all depends on quality and car manufacture. ~Ryan
Good technique. I use a stethoscope I drilled and added a section of 3/16th brake line to for checking exhaust leaks. Works for intake leaks, pulley noises and wind leaks in weatherstripping as well in many cases.
Yup, I got a cheap, disposable stethoscope from a friend who works at a hospital. The listening pad simply has a barb that fits into the hose. Just yank the pad out, and boom, already got the open end of a vacuum hose right there, lol. I love it.
I have a brand new full exhaust and still have po420. High voltage for switch time calculation is my mode 06 code thats popping up. Im guessimg the bank 2 o2 sensor is out of spec? It is original with 143000 miles. My bank 1 is new. I ordered a new rear o2 sensor. If it dont fix it, ill do the o2 spacer trick i quess.
Thanks for sharing your knowledge, it's very helpful. When I was working for General Motors in Mexico, I visited a GM assembly plant at Janesville Wisconsin. It was an awesome experience. Now I live at El Paso Texas.
Nicely explained, really liked the tip for finding the exhaust leak - have you thought about an induction heater - probably okay with the torch for an exhaust but saves a load of worry about melted wiring, hoses and plastics.
Hey Fraser, thanks for watching!!! I have thought about them a lot. I'd really like to get my hands on one, but I also struggle pulling the trigger due to the cost. I have a torch, it does 98% of what I need. Brake lines and fuel lines would be nice to have that inductive heater for sure though. Someday! Mike Becker, Senior Instructor
