girohead, so yours ended up being the cat then. OK well i really don't want to spend time puling out the intake manifold and putting in a new gasket when i don't even know if that will clear my P0420, I might as well start looking in to a cat. Thanks for the info, I guess i can try the soapy water spray first.
Carbon build up in the engine can also trigger the code as I own a 2014 Jeep Grand Cherokee Laredo I used Seafoam Intake Cleaner and after it blew all the carbon out the check engine light turned off and never came back on
Another possible reason for getting PO420 code that is not mentioned....an exhaust leak somewhere that screws up the "comparison" signal between the upstream and downstream O2 sensors.....causing them to say the cat is working below efficiency. One place to look beside obvious rust holes in the piping is the first flange gasket at the exhaust manifold. If this leaks, it screws up the readings and causes the code.
How much will the dealership or a local garage charge for diagnostic and fix? Everytime I go to one with a check engine light, they are magically able to charge upwards of $1000 for a fix, no matter what the issue is.
Very professional and absolutely thorough. I've been wrestling with P0420 for most of the year and found these ideas individually. It's nice to see them altogether in a very professional presentation. I'm finally ready to order a cat, but I called the manufacturer and he agreed that it was often not the cat - but I've looked at all these others already. So frustrating, mainly because my cat is welded inline so I can't even check it. Alldata points to bad cat, but I keep thinking it's something else.
My 2014 Ford Explorer Police Interceptor 3.7L was reading P0420 P0430, and also pending codes for them. Found hot air flow from a leaking gasket after the catalytic converter to the muffler. Replaced the gasket, weld the cracks between muffler and pipe. Codes are gone, waiting for sensors to be ready again.
Changed the catalytic converter but still the check engine light is on , and my main problem the is shaking under the driver seat between speed of 10-40
What problems is it causing? I guess if you leave the cat on it’ll eventually plug all the way up and melt down🤷🏻♂️ The nice thing about the non fouler is that you can pull the o2 sensor far enough out of the exhaust stream to get away with no catalytic converter.
It is a great way to help me understand the P0420 on my Dodge. However, if you eliminate the music from the video the information will be projected much clearly.
@@happyjack8952so you obviously don’t have the brain capacity to relax and absorb the information with the music in the background. I found the music along with the vid EXTREMELY informative along with entertaining. Keep your BS to your self and get a life.
I have a 2007 nissan altima with 214k miles and it's showing the same code p0420 i haven't use the catalytic cleaner yet but i'm going to try that next to see if i can pass inspection. My code reader was throwing a bank 1 sensor not ready so hopefully this helps.
Never use the spark plug gapper itself against the electrode to bend the ground tab as shown in this video. Could easily damage the electrode. Bend the ground tab from the back of it with a proper gap adjustment tool or carefully with needle nose pliers if the tool isn't available. Use a wire loop type feeler gauge on exotic metal plugs for proper gap setting to prevent damage. Most wire loop feeler gauges have a ground tab bender included.
Please, I have a 2004 Fiat Sienna car, and I have a problem with it. When I did the diagnosis, I got code p 1619. I want to know what this means, please.
And more information about that meet word to word everyone who got fined for exhaust leaks or modified exhaust in the meeting congress everyone everyone has access to sue the EPA because they was actually lying about it was law congress never signed bill for EPA and there not law maker's
I have a 2012 nissan versa and I got this code p0420 catalyst system efficiency below threshold bank 1, I've tried cataclean and it didn't work. What should I try next?
Got a 2004 Toyota Highlander with p0420 code. Took it to a shop and they tested o2 sensors - both are good. But I have no symptoms of a bad cat other than the code itself.
I bet it's more likely the misfires polluting the cat to cause the 420. I'd fix the misfire first (my case was old coil pack boots) then try cleaning the cat. But some say backpressure could be an issue with some cats, but I think chemical damage is more often than physical melting. Just my two cents.
Hi Raul, kindly inspect the exhaust manifold, gaskets, and exhaust pipes pre-catalytic converter for any leaks. Then check if there's an issue with the voltage reading of the downstream O2 sensor.
Thank you for your feedback! If there's no other code that register along with this code, we suggest following the tips/solutions provided in our video on how to fix this code. Hope this helps!
I have replaced the Cat twice and the upstream O2 sensor and check engine light came back on after 300 miles and error code P0420. I passed inspection before the light came back. The mechanic advises flushing the computer as the P0420 code is stored in the memory and needs to be removed. Any advice? Thanks
I have a 2017 Hyundai accent and it shows this code and a p0335. Sometimes it will crank with no issues, but there are times when I have to tap the gas pedal for it to start. Any idea of what it could be?
Very thorough video, thank you. I have this problem with a 05 Subaru legacy 2.5i, I really do not want to replace cat if I don’t have to. Can a garage run diagnostics to pinpoint the problem? And also I gave a California emissions car but don’t live in California if I had to replace cat with aftermarket do I have to get a California emissions cat, cause they are considerably more expensive or will a non cal emissions cat work?
Sorry most of this is BS. And spacers do not fix the problem just take the sensor out of the flow of exhaust so it will not longer read the exhaust values. And it will not work in cars after 2012 because they got wise to this and set a program in the computer to detect it. If your check engine lite starts flashing while you are driving pull over and shut the engine off and get the car towed or keep driving and ruin the cat.
I really enjoyed watching your videos, very useful. I have lexus is250 2009 and I can sense rotten eggs smell when I drive hard or speed up quickly. What are the problems?
Hello Sir ! I have two code PO420 and PO430 on Mazda CX 09 2016 engine size 3.7. Engine light is on and Recently passed emission test . Is this possible convertor damge or I need to replace sensor only ? Because I have cleared emission test with this code.
Good afternoon please I have Toyota Camry 2006 model there is no catalyst in inside the two catalyst is remove I wasting gar fuel ⛽ I want to know maybe is catalyst dat cause it pls
2011 Chevrolet Traverse LS 3.6L V6. 198000km. P0420. The code shows up intermittently. No driveability issues yet. It disappears after putting fuel system / exhaust cleaners. Questions: 1. Can I keep doing this for 2 years and not expect damage to the engine? If I do an exhaust restriction and there's no restriction, I should be OK right? 2. Can P0420 mean my engine is failing?
@@nondainc Yes its a lone code. No drivability issues. The o2 sensor 2 follows o2 sensor 1. We don't do emissions testing where I live. I used to have a p0301 code caused by the ignition coil being wet but that has been resolved.
Thank you for the great video and very specific checks for this issue. I have a 2009 chevy cobalt with a new cat converter but i keep getting the 0420 code. I have replaced everything but i have not tried the O2 spacer. Ill give it a shot and report back. Thanks!
@Str8blastn713 Htx south sorry bud this did not work for me. There isn't enough space between the oxygen sensor and the floor board. I was not able to out both foulers on.2009 chevy cobalt LS
Hi, I have a question about P0420. I have2013 nissan pathfinder. My check engine light pumpa up with code P0420 but after a while it's corrects it self and the light goes off. It did that 4 times already. I was wondering if it means anything?
Hi Emrah, this code refers to "Catalyst System Efficiency Below Threshold" which is often triggered by a faulty O2 sensor (upstream side of the catalytic converter). We suggest checking the exhaust for leaks and testing the O2 sensors if functioning properly.
Hello, as you are receiving more than one error code, we suggest getting your vehicle visually checked by your local mechanic for further diagnosis. Thanks for watching!
I got a 2003 s10 changed all three 02 sensors. The cat was bad so I bung a test pipe and place the brand new sensor in do you think it’s because of how I tried to by pass having a cat
Hello, can you please provide us with your vehicle's year, make and model so we can provide you information specifically for your vehicle's make and model?
I have a 2015 Mazda 3 touring made in Japan with these codes and there titles any idea what it means 1).1 permanent trouble code P0421 "catalyst 1 efficiency below threshold bank 1, 2).1 power control module code P0421-00 status :MIL/CONFIRMED/PENDING -catalyst 1 efficiency below threshold bank 1: no sub type information
Hi Meshaf, since we are against having the catalytic converter being removed (to comply with air emission standards that were set for safety environment), we're afraid we couldn't provide any solution in this case. We suggest placing a new cat as well as checking the O2 sensor, O2 sensor wiring, and inspecting for exhaust leak.
You have to completely decode O2 sensors for your ECU, but then car will run on standard map. It is never good idea to get rid of catalytic converter. There is a O2 sensor emulator. That you can add to your engine harness. That way u can "cheat" ecu.
Hi Ahmed, you may head over to this link for your concern. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-OQVUaOrziUo.html Kindly check the condition of the following and repair/replace if necessary: Transmission fluid/filter, wiring/connectors, transmission pump, TCM, output speed sensor/input speed sensor and inspect for transmission fluid leaks.
I have a 2020 Mitsubishi outlander sport SE, and replace my catalytic converter, and 02 sensor. my service engine light was on and once the put the 02 sensor its went off but came back on the next day bought to Mitsubishi and it went off but came back on again.
I have the same vehicle except it is the AWD XLT version, replaced o2 sensors, replaced ignition coils, replaced spark plugs, still had major issues. Took one of the o2 sensors out and looked inside the cat and it was completely shattered. It’s a pain in the a$
Hi i have a golf 5 1.4 fsi and i have check engine code p0420 i have change oxygen sensor and the car is the same and sometime car gassing up alone help me
Hello, if there's no other codes that register along with this code, then we suggest following the tips/solutions provided in our video on how to fix P0420. Hope it helps!
I have a 2015 Honda Pilot. Last week the check engine light came on and I took it to my mechanic. He didn’t tell me the code. He said “engine running lean” and replace the air filter. It was fine all week. Last night it came on again. Went to autozone and got PO420 (cat sys efficiency below threshold bank 1. Can I drive it for a day or two until I can get to mechanic? Will it hurt to try cataclean? I know it might not work. But it won’t hurt anything right? I still need to have it checked. It has some trouble starting for a while. No bad smells, noises, or smoke. Passed inspection in February. Has 154000 miles. Slight drop in fuel efficiency. No performance issues. Always use cheapest gas. Should I try better gas? What octane and from who? I usually do Circle K.
i've been having that code for years. It just means your cat might be going out. You won't pass smog test tho with the code. For honda you might have to replace OEM cat which is very expensive. You can try to do from following above video. Cats only last up to 100k to life the car. You never know.
Hi Regina, if there's no other codes that register along with this code, we suggest following the repair procedures provided in our video. Hope it helps!
I have codes p0420 and p0132 on a 2015 Chevy Sonic LT 1.8L with no check engine light on . I have been experiencing the car shutting off while driving lost of power in it , and jerks badly when accelerating. Any idea of what this could be ? Please and thank you .
Hello, as you are receiving more than one error code, we suggest getting your vehicle visually checked by your local mechanic for further diagnosis. Thanks for watching!
Have u done anything to fix this or got it diagnosed? Im experiencing a p0420 code with my 2014 chevy sonic ltz. Im experiencing the same issues except for the car shutting off
You cOuLd chEcK mORe possibLe caUseS: Faulty Three-way Catalyst Converter Bank 1 Exhaust Tube Intake Air Leaks Faulty Oxygen (O2) Sensor Faulty Fuel Injector(s) Leaking Fuel Injector (s) Faulty Spark Plugs Improper Ignition Timing Faulty Engine Control Module (ECM) Dirty Air Filter
OMG how dumb can you get! The only O2 sensor that monitors the cat is downstream from the cat so how is the upstream sensor going to monitor the cat? The upstream sensor only monitors if the engine is running rich or lean and nothing else. If you put a spacer upstream than the sensor doesn't know if the engine is rich or lean and really sets a lot of codes.
My 2011 accord coupe shows the p0420 code bank 1 just yesterday I started to hear a rattling noise coming from 7nder the car it comes and goes away you think mt cat is done for
Hi Eddie, it's an issue with the catalytic converter. If this is the only code that you're receiving then you can follow the guide/solutions provided in our video on how to fix P0420.
@@nondainc initially the only code I came up with was P0420 and changed both 02 sensors but now it bunched up with my MAF Sensor despite me just getting a new one recently. I'm really debating just spending the money and getting a new Cat even tho I don't want to at all
Hello Sir, I really like your vedios, its very helpfull, but i have a qustion. I have an Audi A6 2014 2.0 torbu and Ihave a problem that my car has a delay with first gear & retern (automatice gear) with cold start & blowing smoke from the exust when I start moving slowly the car jumping needs to turns off Iwent yo the service center they talled me I have a code P0011 so I have to change the intake camshaft and I know that they have no experiance to repair Audi cars So please can you helpe me with that ? what i have to do
Hi Ara, there are multiple factors that could be contributing to the appearance of this code particularly for your vehicle's make/model. We suggest checking the condition of the Intake Valve Timing Control Solenoid Valve/harness or electrical connection, condition of the camshaft position sensor/ harness or electrical connection, engine coolant temperature sensor and the crankshaft position sensor.
@@nondainc Thank you so much for your help, I have already toke off the CAM& I found the connection clip of the Camshaft Adjuster Magnet full of oil, is that a reason for this fault?
@@nondainc I’ve got a 07 Mini Cooper S. Literally going through a rough patch. Replaced coils, plugs, 02’s, carbon cleaning and oil change. Still rough starts and on and off limp mode. Little to no boost. Muffler pro said the cat is fine. 🤔🤷🏻♂️
Good day, my 2008 Toyota Camry XLE V6 check engine light popped up when I was on top speed traveling, I began to notice a little bit increased sound when I start the engine. I used a scanner and it detected P0420 low catalyst efficiency below threshold bank 1… what do I do? Thanks
Hello, kindly inspect the exhaust manifold, gaskets, and exhaust pipes pre-catalytic converter for any leaks and repair it right away. If the issue will continue to persist, check if there's an issue with the voltage reading of the downstream O2 sensor. Since you are also hearing a noise when starting the engine, we suggest checking the temperature of the pipe before and after the catalytic converter using a thermal gun as this will easily help you know if the catalytic converter or the down stream Oxygen sensor is faulty.
So after changing the exhaust flex, removing and reinstalling the exhaust manifold carrying the catalyst after thoroughly washing it together with the O2 sensors, check engine totally disappeared and performance greatly improved. 👍🏾
Hi Misty, as long as there's no other fault codes registering together with code, it should be fixed immediately. But we'd like to clarify that this isn't the only fix for this code as there's also other parts to be checked.
Hi! I have a 2011 Buick Enclave CXL 2fwd I’m getting a catalyst system efficiency DTC severity 2 of 3 repair immediately. Is it my catalyst converter or could it be my water pump? What should I do clean it or replace it??
Hi Kimberly, have you checked if there's an exhaust leak? You need to test the O2 sensors (upstream side of the catalytic converter) and the catalytic converter to pinpoint what's causing the issue.
@@nondainc Hi! I have a 2016 Audi A1 Sportback, I have done basic maintenance, replaced oil and filters. Checked for exhaust leaks. I am using high quality fuel. I get the P0420 error. I have not yet tried all solutions here, but I just find it weird that I don't get any symptoms. The car operates normally and if it wasn't for the error I would say it was 100% fine! Without symptoms it's much harder to diagnose this problem. I think I will change spark plugs next, I don't think they've ever been changed.
