Kia code p0420 - HYUNDAI KIA CODE P0420 CATALYTIC CONVERTER FIX, ENGINE LIGHT ONIf you have Hyundai or Kia and you have engine light and code P0420 Catalyst System Efficiency...

 
Last spring on cold mornings the check engine light would come on with the P0420 code when I check it with my code reader. Then nothing all summer but with the cold weather back, the light is coming on more frequently. ... Kia Soul 2015 2.0 litre EX GDI Alien Green II Pearl ~73K km (45K miles) Michelin CrossClimate tires.. 60fps yuzu

December 22, 2022 by Jason. This page is meant to help you troubleshoot the Kia Sorento P0420 trouble code. It covers the P0420 code’s meaning, symptoms, …Code P0420 Description. The Engine Control Module (ECM) uses sensors mounted in front of and behind the Three-Way Catalytic Converter (TWC) to monitor its efficiency. The first sensor, the air-fuel ratio sensor, sends pre-catalyst information to the ECM. The second sensor, the heated oxygen sensor, sends post-catalyst information to …KiaP0420 Kia DTC P0420 Make: Kia Code: P0420 Definition: Catalyst Efficiency Below Normal (Bank 1) Description: DTC P0130, P0133, P0134, P0135, P0136, P0139, P0140 and P0141 not set, engine started, engine running in closed loop at a speed of 45-60 mph for 2-3 minutes, and the PCM detected that the rear HO2S and front HO2S voltage amplitudes were too similar.South Jersey catalytic converter shopThe P0420 code on a Hyundai refers to a diagnostic trouble code that indicates a problem with the efficiency of the catalytic converter. The code specifically identifies that the catalytic converter is not performing optimally and may be failing to reduce harmful emissions. This issue can affect the vehicle’s performance and fuel efficiency.Kia and Hyundai are not a single corporate entity. They are sister companies, both of which operate out of South Korea. Both Kia and Hyundai are known for producing inexpensive hig...Save up to 80% today with the top Western Digital coupon codes from PCWorld. 15% off SSDs, hard drives & My Passport. 15% off Western Digital Student Discount. PCWorld’s coupon sec...P0420 is a catalytic converter insufficiency code. What can trigger the cel. An Oxygen sensor fault , worn cat , maf issue , etc , You run certain test to pinpoint the issue. An inexpensive code reader with live data , can be use to look at certain pids of info to help pinpoint your diagnosis. waddy. Like.P1000 Readiness Function Code. P1115 Engine Coolant Temperature Signal from ECM to TCM. P1121 Throttle Position Sensor Signal Malfunction from ECM to TCM. P1170 Front Heated Oxygen Sensor Stuck. P1195 EGR Pressure Sensor (1.6L) or Boost Sensor (1.8L) Open or Short.If your Soul is misfiring or the exhaust timing is off, this can affect the gasses that are actually going to the O2 sensors enough to cause the P0420 code to register. If there’s a noticeable exhaust leak coming from the vehicle it can change what the O2 sensors register enough to throw the P0420 code.P0420 KIA 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.#1 · Nov 2, 2019. 2015 Soul, 1.6 L, V4 - 93,000 + mi. Code P0420 Catalyst operating below minimum threshold. P0420 is an all around code dealing with emmisions. To learn more about this code, view YouTube videos of …P0420: betydning, årsager, reparationer. P0420 kode tydning. P0420 fejlkoden ndikerer at katalysatoren ikke fungerer effektivt og sædvanligvis, at den skal udskiftes. Hvis det genereres, skal du få udført en diagnose af din motor og brændstofindsprøjtning, tænding og udstødningssystem. Årsager til fejlkoden P0420.The most common fix for P0430 in the Kia Sorento is a new catalytic converter, followed by replacing the Oxygen sensor. Before taking your Sorento into an exhaust shop for a new catalytic converter, let’s ensure that’s what you need. Here’s a good P0430 diagnostic order for the Kia Sorento: 1. Check for Other Codes.If you’re a car owner, there’s a good chance that at some point you’ve encountered the dreaded check engine light. Code P0420 is a generic diagnostic trouble code that indicates an... P0420 is a diagnostic trouble code (DTC) for "Catalyst System Efficiency Below Threshold (Bank 1)". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic ... jeremiahchub. 56 posts · Joined 2017. #7 · Jun 12, 2019. Also, you may want to try replacing the FUEL pressure regulator itself. that code also goes with that as well. 2010 Molten Red Kia Soul +, 2.0L Beta II Engine, Mitsubishi 5-Speed (Yes the transmission real is made for Kia by Mitsubishi), and getting used to So Cal.P0420 KIA Code - Warm Up Catalyst Efficiency Below Threshold Bank 1. Table of contents. What does this mean? What are the Possible Causes of the DTC P0420 KIA? NOTE: The causes shown may not be a complete list of all potential problems, and it is …P0420: Catalyst System Efficiency below Threshold – Bank 1. P0422: Main Catalyst Efficiency below Threshold – Bank 1. P0440: Evaporative Control Malfunction. ... Please help. I am getting a P0261 code with my 2012 Kia Forte Ex Sedan 2.0. The car is running worse after replacing cylinder 1 fuel injector. I’m going from Montana to Oregon ...My car is showing a P0420 code with CEL on the dash and while I was doing some research as to the possible causes and what not it was saying that the most …Here are some steps to fix a P0420 code Honda Accord. First, remove the O2 sensor and pour 4-6 ounces of seafoam into the opening, replace the sensor, and leave it overnight. Reset the code and then continue driving. Increase the gap between the oxygen sensor and the converter using a spark plug non-fowler.The most common fix for P0420 in the Kia Borrego is a new catalytic converter, followed by an O2 sensor replacement. Before taking your Borrego into an exhaust shop for an (expensive) new catalytic converter, let’s ensure that’s what you need. Here’s a good P0420 diagnostic order for the Kia Borrego: 1. Check for Other Codes.P0420 Catalyst System Efficiency Below Threshold. How to diagnose, repair, and info on symptoms and causes of a P0420 engine code which means the catalytic converter is no longer performing at a normal level. www.obd-codes.com. Several possible issues to check. eGAK009.P0420 Kia Catalyst System Efficiency Below Threshold Bank 1. As the code description implies the P0421 Kia code means that the vehicle’s control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but ...About the only things that could cause P0420 are an actual inefficient catalytic converter or a bad O2 sensor. Another possibility if you have an exhaust leak upstream that occasionally goes under vacuum, I could see sucking oxygen into the exhaust and maybe triggering the code. I don't know how likely that one is on a Kia. 2016 Kia Soul ! M.P0420 KIA Code - Warm Up Catalyst Efficiency Below Threshold Bank 1. Table of contents. What does this mean? What are the Possible Causes of the DTC P0420 KIA? NOTE: The causes shown may not be a complete list of all potential problems, and it is …Kia Motors uses designs from the Global Engine Manufacturing Alliance. GEMA is a conglomerate of several large automotive brands, such as Hyundai and Mitsubishi, that allows its ve...P1000 Readiness Function Code. P1115 Engine Coolant Temperature Signal from ECM to TCM. P1121 Throttle Position Sensor Signal Malfunction from ECM to TCM. P1170 Front Heated Oxygen Sensor Stuck. P1195 EGR Pressure Sensor (1.6L) or Boost Sensor (1.8L) Open or Short.If you’re in the market for a new car, it’s important to understand the factors that influence the prices of different models. When it comes to Kia vehicles, there are several key ...Just click in the upper right corner where it says Login/Join. We look forward to your continued parcipitation. Check engine light. P0420. P0420 Catalyst System Efficiency below Threshold. 2018 Niro LX HEV with just over 34,000 miles. So the catalytic converter for some reason is not working as it is supposed to.The most common fix for P0430 in the Kia Sorento is a new catalytic converter, followed by replacing the Oxygen sensor. Before taking your Sorento into an exhaust shop for a new catalytic converter, let’s ensure that’s what you need. Here’s a good P0430 diagnostic order for the Kia Sorento: 1. Check for Other Codes.=====Claim your FREE engine code eraser 👉 https://free.nonda.co 👈=====Engine Code P0420 Saving Repair Parts:C...Kia and Hyundai are not a single corporate entity. They are sister companies, both of which operate out of South Korea. Both Kia and Hyundai are known for producing inexpensive hig...How to diagnose code P0420 on a Kia Rio. Typically, you'll find out about P0420 because your malfunction indicator lamp or "check engine light" turned on & you or a mechanic diagnosed the problem with an OBD II code scanner like this one from Bluedriver. You may experience a very slight reduction in engine power from reduced …P0420 KIA 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.After a Kia and Hyundai agreed to a $200 million car theft settlement, it's still hard for vehicle owners to get affordable auto insurance. By clicking "TRY IT", I agree to receive...However, on average, the repair costs for addressing the P0420 code in a Kia Soul can range from $200 to $1,000. In conclusion, the 2015 Kia Soul P0420 code has been a topic of concern among car enthusiasts and mechanics alike. This diagnostic trouble code indicates a malfunction in the catalytic converter efficiency, which can lead to ...P0420 is a diagnostic trouble code (DTC) for "Catalyst System Efficiency Below Threshold (Bank 1)". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic .../nwsys/www/images/PBC_1251019 Research Announcement: Vollständigen Artikel bei Moodys lesen Indices Commodities Currencies StocksYou've learned to code, but now what? You may have some basic skills, but you're not sure what to do with them. Here's how to choose and get started on your first real project. You...Failed catalytic converter: A failed catalytic converter is the most common cause of a P0420 code. While some catalytic converters fail from age or high milage, the majority of failures are a byproduct from an underlying issue. The most common issue being an excessive rich condition caused by a misfire or fuel trim problem.الكود p0420 من أكثر أكواد الاعطال شيوعا في جميع السيارات يرتبط هذا الكود بتدني كفاءة علبة البيئة- الكتلايزر ...Sometimes, when you see O2 sensor related codes, fixing those might also fix the code P0420. If the code P0420 is the only code present, visually inspect any exhaust leaks before the rear O2 sensor. An exhaust leak may mislead the O2 sensor and trigger the code. If you find any broken, cracked or disconnected hoses, replace them …P0420 Catalyst System Efficiency Below Threshold. How to diagnose, repair, and info on symptoms and causes of a P0420 engine code which means the catalytic converter is no longer performing at a normal level. www.obd-codes.com. Several possible issues to check. eGAK009.P0420 is a catalytic converter insufficiency code. What can trigger the cel. An Oxygen sensor fault , worn cat , maf issue , etc , You run certain test to pinpoint the issue. An inexpensive code reader with live data , can be use to look at certain pids of info to help pinpoint your diagnosis. waddy. Like.Code Search and confirm DTC P0420 or both P0420 and P030X is/are stored (Active, ... Before attempting an ECU upgrade on any Kia model, make sure to first determine whether the particular model is equipped with an immobilizer security system. Failure to follow proper procedures may cause the PCM to become inoperative after the upgrade and any ...Code P0420 Description. The Engine Control Module (ECM) uses sensors mounted in front of and behind the Three-Way Catalytic Converter (TWC) to monitor its efficiency. The first sensor, the air-fuel ratio sensor, sends pre-catalyst information to the ECM. The second sensor, the heated oxygen sensor, sends post-catalyst information to …About 1000 miles ago I started getting both P0420 and P0430 codes. I reset, but they came back in a week and since then I have been getting either a p0420 or a p0430 but not both at the same time. ... Kia-Forums.com is an independent Kia enthusiast website owned and operated by VerticalScope Inc. Content on Kia-Forums.com is …P0420 means the catalytic converter is not efficiently removing pollutants from the exhaust. Your car won’t pass an emissions test. A bad catalytic converter isn’t a hazard to the driver but it can …The Kia Code P0011 refers to a specific fault code that indicates an issue with the Variable Valve Timing (VVT) system in a Kia vehicle. When this code appears, it means that there is a problem with the VVT system’s Camshaft Position – Timing Over-Advanced or System Performance Bank 1. This is typically due to a mechanical fault or … =====Claim your FREE engine code eraser 👉 https://free.nonda.co 👈=====Engine Code P0420 Saving Repair Parts:C... P0420 Kia Catalyst System Efficiency Below Threshold Bank 1. As the code description implies the P0421 Kia code means that the vehicle’s control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but ...Code Tech Notes. As the code description implies the P0430 code means that the vehicle's control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases the catalytic convert needs to be ...The P0420 code in a Kia Soul will often be thrown one of your oxygen sensors are not functioning properly. Typically, the code will be triggered by the upstream oxygen sensor (before the converter). OBD-Codes › p0326Common Reason: Code P0420 is often related to a bad catalytic converter. P0420 means the catalytic converter is not efficiently removing pollutants from the exhaust. Your car won’t pass an emissions …I got a P0420 code on my 2014 Kia Soul. It states warm up catalyst efficiency, below threshold Bank 1. The car runs fine accept when after I stop at a light, and press the gas pedal, the RPM goes to 3, then back down to 2. Also when it's raining, my windows fog up if I turn on my heat but clears up if I turn on my air conditioner, even when it ...As of 2015, Kia cars are produced at 14 assembly and manufacturing locations located in eight countries. Kia produces over 1.4 million vehicles annually, a large portion of which a...When the P0420 code appears, the catalyst system efficiency is below the threshold for a particular engine bank, often referred to as Bank 1. This code is related to the vehicle's catalytic converter and oxygen sensors. The primary purpose of a catalytic converter is to reduce harmful emissions from the engine by converting toxic gasses, such ...Like. R. rhandwor. 1284 posts · Joined 2011. #8 · Mar 4, 2014. P0420 Code frustation. If your scanner is that good the front sensor front of Cat. should have a fluctuating wave form. The sensor behind cat. should be more steady wave form. Bang on …Oct 6, 2022 · I got a P0420 code on my 2014 Kia Soul. It states warm up catalyst efficiency, below threshold Bank 1. The car runs fine accept when after I stop at a light, and press the gas pedal, the RPM goes to 3, then back down to 2. Also when it's raining, my windows fog up if I turn on my heat but clears up if I turn on my air conditioner, even when it ... Sometimes, when you see O2 sensor related codes, fixing those might also fix the code P0420. If the code P0420 is the only code present, visually inspect any exhaust leaks before the rear O2 sensor. An exhaust leak may mislead the O2 sensor and trigger the code. If you find any broken, cracked or disconnected hoses, replace them and fix the code.Check engine light came on, Code P0420 Catalyst System Efficiency Below Threshold (Bank 1) poped up on my scanner. Cleared the code and have driven it over 50kms, no issue (low or weaker performance). I have a 2013 Rio with 143000 kms. Warranty on emmision system ended at 130,000 kms. Hope it doesn't return, but from what I read …Apr 12, 2021 · P0420: Catalyst Efficiency Below Threshold. Related Vehicles: 2012-2018 Veloster 1.6L GDI. Notes/Hints: Check the downstream O2 sensor. If the sensors signal is dropping when it shouldn't, or reading low voltage during WOT, replace it first, clear code (s) and recheck before condemning the catalytic converter. Just click in the upper right corner where it says Login/Join. We look forward to your continued parcipitation. Check engine light. P0420. P0420 Catalyst System Efficiency below Threshold. 2018 Niro LX HEV with just over 34,000 miles. So the catalytic converter for some reason is not working as it is supposed to.My daughter has a 2015 Kia soul with the 1.6. 106,000 miles and it’s throwing the p0420. I reset it and it comes back. I ran the vin and it shows no active recalls. Is there a way to verify Kia actually already did the converter or does the recall notice state to take it to a Kia dealer when the code comes on.P0420: merkitys, syyt, korjaukset. Vikakoodi P0420 tarkoittaa katalysaattorin tehon moottorin puolella 1 olevan alle raja-arvon. Auton katalysaattoria tarvitaan moottorin polttoprosessin aikana syntyvien haitallisten päästöjen hajottamiseen ja näin se on tärkeässä roolissa ajoneuvon päästöjen vähentämisessä.kiaguy002. 1595 posts · Joined 2015. #7 · Feb 5, 2020. I've never read an account of spark plugs having any effect on a P0420, one way or the other. Yes, bad plugs causing misfire will eventually trash out a cat and cause the P0420, but once that occurs, it's then too late for new plugs to 'fix' the cat.Mar 18, 2024 · P0420 code. I have a 2016 Kia Soul 1.6L, we have had a run around with Kia over these codes. We first had the Knock Sensor put in and after that the engine light would come on and off from time to time. We contacted the Kia dealer we purchased it from and spoke with the maintenance dept manager. He said that when the seasons change that it ... The Ole P0420. Tags ... I believe the key thing to look at for a P0420 code is the downstream O2, or bank 1 sensor 2 B1S2. ... see i havent replaced my cat converters yet but i have the o2 sensors but the light goes on and off . kia said it was the clogged cat but my dad as well as 2 other mechanics said the way its driving and the fact no ...When the P0420 code appears, the catalyst system efficiency is below the threshold for a particular engine bank, often referred to as Bank 1. This code is related to the vehicle's catalytic converter and oxygen sensors. The primary purpose of a catalytic converter is to reduce harmful emissions from the engine by converting toxic gasses, …Every year, millions of people head out to enjoy Black Friday. This time of the year gives you an opportunity to save a lot of money. Don’t hesitate to put a new ride on your holid...P0420: betydning, årsager, reparationer. P0420 kode tydning. P0420 fejlkoden ndikerer at katalysatoren ikke fungerer effektivt og sædvanligvis, at den skal udskiftes. Hvis det genereres, skal du få udført en diagnose af din motor og brændstofindsprøjtning, tænding og udstødningssystem. Årsager til fejlkoden P0420.Arrival has gone from stealthy electric vehicle startup to prospective public company in a span of a year. The UK-based company, which operated in relative secrecy for several year...If you are in the market for a new or used car in Tulsa, OK, look no further than Midtown Kia. As one of the leading dealerships in the area, Midtown Kia offers a wide range of veh...The P0420 code indicates that your vehicle’s powertrain control module (PCM) monitors the poor efficiency of the catalytic converter at Bank 1. This code may also be triggered due to a bad catalyst or a false alarm caused by a faulty oxygen sensor at Bank 1. Basically, Bank 1 and Bank 2 are the two sides of the engine.This page is meant to help you troubleshoot the Kia Venga P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table …P0420 P0430 DTC codes? Want to clean your catalyst without removing it? Are you experiencing problems with the catalytic converter in your car? You will disc...The P0420 code indicates that your vehicle’s powertrain control module (PCM) monitors the poor efficiency of the catalytic converter at Bank 1. This code may also be triggered due to a bad catalyst or a false alarm caused by a faulty oxygen sensor at Bank 1. Basically, Bank 1 and Bank 2 are the two sides of the engine.Code P0420 "catalyst system efficiency below threshold." Local Kia dealer's first available slot for a diagnostic appointment is one week from now; they charge …Aug 18, 2023 · Tech Notes. As the code description implies, the P0420 code means that the vehicle's Engine Control Module (ECM) has detected that the Three-way Catalyst Converter is not working properly (it is not as efficient as the factory expects). Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases, the Three-way Catalyst ... This page is meant to help you troubleshoot the Kia Telluride P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table …Can you smoke in a leased car? The policy varies by dealer. We have the details on smoking in a leased car from Chevrolet, GM, Kia, Toyota, and more. Jump Links Smoking in a leased...May 11, 2019 · Here’s a good P0420 diagnostic order for the Kia Spectra: 1. Check for Other Codes. The first thing you want to do when trying to fix P0420 in the Spectra is to verify there aren’t any other trouble codes. Three types of codes can give clues as to what’s going on with your car. Misfire Codes. The most common fix for P0430 in the Kia Sedona is a new catalytic converter, followed by replacing the Oxygen sensor. Before taking your Sedona into an exhaust shop for a new catalytic converter, let’s ensure that’s what you need. Here’s a good P0430 diagnostic order for the Kia Sedona: 1. Check for Other Codes.The code P1233 is showing that the low pressure pump is having issues keeping up with the demand from the high pressure pump. This will cause the running issue you are experiencing. The P0420 may be the results of the misfire codes. I would check the low pressure fuel pump and likely replace it, then clear the codes and see what comes …Posted by u/That-Mall-8347 - 8 votes and 7 commentsIf you’re in the market for a new car, it’s important to understand the factors that influence the prices of different models. When it comes to Kia vehicles, there are several key ...Like. R. rhandwor. 1284 posts · Joined 2011. #8 · Mar 4, 2014. P0420 Code frustation. If your scanner is that good the front sensor front of Cat. should have a fluctuating wave form. The sensor behind cat. should be more steady wave form. Bang on cat. if noisy replace.

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kia code p0420

The most common fix for P0430 in the Kia Sedona is a new catalytic converter, followed by replacing the Oxygen sensor. Before taking your Sedona into an exhaust shop for a new catalytic converter, let’s ensure that’s what you need. Here’s a good P0430 diagnostic order for the Kia Sedona: 1. Check for Other Codes.Save on your password security with Keeper Security promo codes. Get the latest on Keeper Security promo codes, coupons, and May sale on PCWorld. PCWorld’s coupon section is create...How to diagnose code P0420 on a Kia Niro. Typically, you'll find out about P0420 because your malfunction indicator lamp or "check engine light" turned on & you or a mechanic diagnosed the problem with an OBD II code scanner like this one from Bluedriver. You may experience a very slight reduction in engine power from reduced …=====Claim your FREE engine code eraser 👉 https://free.nonda.co 👈=====Engine Code P0420 Saving Repair Parts:C...Code P0420 KIA Tech Notes. As the code description implies the P0420 code means that the vehicle's control module has detected that the three-way catalytic …The P0420 code indicates that your vehicle’s powertrain control module (PCM) monitors the poor efficiency of the catalytic converter at Bank 1. This code may also be triggered due to a bad catalyst or a false alarm caused by a faulty oxygen sensor at Bank 1. Basically, Bank 1 and Bank 2 are the two sides of the engine.One of the most frequent diagnostic trouble codes (DTCs) that car owners see is P0420. It means that Bank 1’s catalytic converter performance on Bank 1 has been identified by the engine control module (ECM). The catalyst may be at fault for this code, or an O2 sensor may be to blame for a false alert. Understanding the significance of the ...Code P0420 "catalyst system efficiency below threshold." Local Kia dealer's first available slot for a diagnostic appointment is one week from now ; they charge $90.00 to diagnose the problem ; they say there's a 8-year 80,000 mile warranty on the catalytic converter .The P0420 code in a Kia Soul will often be thrown one of your oxygen sensors are not functioning properly. Typically, the code will be triggered by the upstream oxygen sensor (before the converter). OBD-Codes › p0326Or is there no effect on driving it only check engine light is On. DTC Symptom Descriptor P0420 & P04DF. The Catalyst System Efficiency Below Threshold (Bank 1) The most possibly causes. Exhaust system. Downstream oxygen sensor. Catalyst converter. Out-of-range ECT sensor. Exhaust manifold.426 posts · Joined 2014. #3 · Jul 9, 2015. There are a number of things that could be causing this p0420 catalyst efficiency code. The most common thing is the catalytic converter itself is no longer functioning properly. The other likely thing is the rear O2 (oxygen) sensor is no longer working properly..

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