Ford Super Duty (1999-2016) :: P0420 Code - Leak At The Joint Where Exhaust Manifold Meets Pipe Beside The Engine
I have a 2011 F350 CC long box 4x4, with a 6.2, 93,000 km on it. I periodically get a P0420. I clear it and sometimes it comes back in 10 or 20 KM and sometimes it comes back in a couple hundred km. Been doing this for about 800 KM.
Yesterday I got an exaust leak at the joint where the exaust manifold meets the pipe beside the engine. Checked close, bolts appear intact, leak is on the outboard side blowing towards the frame. Looks like a gasket or donut seal failed.
I am wondering if the catalytic converter was plugged or restrictive, would this cause the P0420 and could back pressure from a restricted catalyitic converter cause the gasket to blow?
Golf V R32 :: Got CEL And P0420 Code After Engine And DSG Flash
I've had both the engine and DSG flash from UM for over a year. The other day I got a cel and a p0420 code. I still have stock dp and oem cats (only Borla cat back). I know the cats are still under warranty (8years 80,000mile). My question is if I bring the car to the dealership for cat warranty will they be able to detect the um flash and use it against me to fix the cat problem?
View 6 RepliesGolf VI R :: 2009 TDI - P0420 Catalytic Converter Code
Does this mean the DPF is shot? I believe its integral with the cat. whats worth checking first?
View 2 RepliesGolf IV / Jetta IV :: Getting Error Code P0420 Intermittently?
I keep getting the error code P0420. Cat below threshold.
I have replace both the front and rear O2 sensors and we reset the check engine light. While driving through the cycles to reset the sensors for them to be ready for DEQ, the check engine light came on again.
I am about ready to buy the Cat Converter, but it is really expensive and if there are any other things that I can try before replacing the Cat I would like to try that first. Any other issues associated with that code, or should I just replace the Cat Converter as my next step.
Golf IV / Jetta IV :: Check Engine Light Came On And Went Away - P0420 Code
MK4 GTi - My check engine light came on a few days ago and when I checked it, it pulled code P0420.
Just this morning, the check engine light went away.
Is this a common issue? Or should I go get it checked just in case?
Golf IV / Jetta IV :: Downpipe Stud Broken And Code Is P0420?
So I recently bought a GTI and started to fix a couple things. It has a P0420 code so I bought a new downpipe to install. Noticed the stock one was missing 1 of the nuts and the stud had broken off. How get this out? Do I need to remove the turbo? Looks like I do need to remove the turbo to use an extractor set.
View 7 RepliesGolf/GTI VI :: Code P0420 / Hesitation At WOT - Fried Catalytic Converter?
Title says it. Cat is done. Threw code p0420 and am experiencing hesitation at WOT. Already replaced my front o2 (cbfa) and now I'm debating whether or not to get a new downpipe. I daily the car and am wondering if keeping the car as is for a while will damage anything. Cts turbo has a sale for a catless downpipe.
View 5 RepliesGolf IV / Jetta IV :: 2003 - Got Error Code P0420 And P0141?
I just bought a 03 2.0 and ive been trying to fix her back up, she is almost there, just waiting on my first gear getter from diesel geeks and trying to figure out why these codes (p0420 and p0141) keep coming back on. Originally it was just a p0420 code so i took out the upstream sensor and cleaned it, then i took out the backstream and after examining it figured it should be replaced.
I went and bought a new one and replaced it, within the next 2 days the check engine light came back on throwing the original p0420 code along with p0141 this time. So i took out the new down stream 02 sensor and took it back to autozone and they swapped it out with a new one for me free of charge. So i put the newest 02 sensor in and then within 2 days, both codes p0420 & p0141 came back on. Two 02 sensor heating wires being bad i feel is a pretty slim chance. What is possibly the cause for these two codes repeatedly being thrown?
Golf IV / Jetta IV :: 2001 - Intermittent P0420 Cat Below Efficiency Code Appears
2001 Jetta 2.0, manual trans
I've been having problems with intermittent P0420 cat below efficiency code. Everything else is fine, no codes, runs great. I tried spacing the post cat sensor back w/ extender bung (after replacing post cat sensor..) and still get the code. I don't hear any rattling or anything to make me think cat is bad physically. I was told by dealer that a code update might resolve for $200 - which got me thinking that that if that was so, it should should be a problem which Feds should be aware.
I searched safercar.gov and found this NHTSA ID Number: 10054864
It's a service bulletin saying that VW made the limits too sensitive and it seems there was a customer satisfaction campaign to update code - pdf on site CSC-10054864-8736
It says:
May 2007
Subject: Emissions Service Action N7
1999-2002 Jetta, Golf and GTI with VR6 Engine
Update Electronic Control Module (ECM) Software for Catalytic Converter Monitoring System Dear Volkswagen Owner: We are writing to inform you of an emissions service action on some 1999-2002 Jetta, Golf and GTI VR6 engine vehicles. Our records show that you are the owner of one of these vehicles.
What Is The Problem? The electronic control module (ECM) software for the catalytic converter monitoring system is too sensitive. This can cause the MIL to come on, and some vehicles may exceed Federal and/or California emissions standards. Also, in some cases this leads to unnecessary catalytic converter replacement. What Will Volkswagen Do? Dealers will update the ECM software.
Golf IV / Jetta IV :: Engine Misfired Twice And CEL Came On For Code P0420 / Inefficient Catalyst
I bought my Jetta almost a year ago, and I've been constantly replacing parts. Unfortunately, my engine misfired twice and the CEL has come on for P0420 which is inefficient catalyst. This is the only code being thrown. I've cleared it like 10 times, but it keeps popping up.
View 9 RepliesGolf IV / Jetta IV :: Error Code P0420 - Catalyst System Efficiency Below Threshold
On my 2002 (AVH) 2.0L 4cyl Jetta I have a persistent P0420 error code: "Catalyst System Efficiency Below Threshold"
I changed the oil, cleaned the Mass Airflow Sensor, replaced the coolant, thermostat, and coolant temperature sensor. But it's still showing up.
OBDII says it could still be:
A damaged or failed oxygen sensor (HO2S)
Downstream oxygen sensor (HO2S) wiring damaged or connected improperly
Damaged or leaking exhaust manifold / catalytic converter / muffler / exhaust pipe
Retarded spark timing
The oxygen sensors in front and behind the converter are reporting too similar of readings
Leaking fuel injector or high fuel pressure
Cylinder misfire Oil contamination
Celica :: 2000 GT - CEL Pop Up / Code P0420
I was just driving and suddenly i had my CEL pop on. I went to pepboys to have them read the code for me and it Came up P 0420. I have been looking up the code and got a few emissions issues but not sure what one to do first. Any link with Main issues for CEL Codes? Or know what it could be?
View 2 RepliesPrius (Gen 2) :: 2007 - Code P0420 Comes And Goes?
I have a 2007 Prius/70,000 miles and live in NY. The Malfunction Indicator Lamp (Check Engine Light) came on back in May when I was visiting Texas and I stopped to have the code read and got a P0420 code - possible emission problem. As I was far from home I took a day to think about what I should do and by the next evening the light had shut off. Driving back to NY the following week the light came on again about 150 miles from home. Once again within a few days it had shut off. End of June I had the same thing happen - this time I took it to a Auto Part store and had them read the codes again. The guy there told me the only thing that showed up was some kind of emission error. Again within a few days the light went off. Just yesterday (August now) the light came on again. I've resisted taking it to the dealer because I know they will charge me $100+ just to plug it in and tell me what I partly already know. I've been reading up the P0420 code online however still have a few questions.
A. Is it normal for this code to go on and off repeatedly without me really doing anything?
B. Is there any way to figure out what the specific issue is without taking it to Toyota?
C. If it is the catalytic converter would I be covered under the Federal Emission Warranty? - which from what I've read is 8 years/80,000 miles?
The following is what the initial code printout read:
Troubleshooting P0420
OEM Brand: Domestic
Definition
Catalyst efficiency low-bank 1
Explanation
The oxygen sensors monitor the Catalytic Converters ability to store oxygen.
Probable cause
1. Catalytic converter defective (failure possibly due to # 2, 3, or 4)
2. Engine misfire or running condition
3. large vacuum leak
4. Engine oil leakage into exhaust-valve guide seals, piston rings
Passat (B5) :: P0420 Malfunction Code
While on business travel, my wife's 2003 1.8T Passat wagon had the MIL illuminate. I had her pull the OBD2 code while I was away, and it came up with P0420. I have been reading up on it, but I have found much in the way of troubleshooting this code. I don't want to just start randomly replacing parts until the light goes away. When I get back I am going to look for exhaust leaks, but barring those what else can be looked for.
View 5 RepliesGTI 337/20th Anniversary :: Keep Getting CEL / Code P0420
I have Unitronics Stage 2, and a 3" downpipe... I keep getting a CEL P0420. I know its about the second o2 sensor, but I don't understand why I am getting the CEL with my chip? Could it be possible that when I put the downpipe back in i reversed the 2 sensors? Or are they the same...
View 5 RepliesCamry :: When Drive Over 80 Mph Within 15 Minutes CEL Comes On With Code P0420
2006 Toyota Camry LE (4 cyl) with 149,500 miles. All maintenance up to date.
Over the past month, anytime I drive over 80 mph within 15 minutes, the CEL comes on with the code P0420. I read the code and erase it. The funny thing is typically I'm getting very good gas mileage during that tankful when the CEL comes on. I've read that it is likely the downstream oxygen sensor and I plan to replace it. (In February, I replaced the air/fuel sensor). My two questions are:
a) What is the part number for the oxygen sensor (non-California emissions)? I want to make sure I get the right part.
b) Why the CEL comes on after travel over 80 mph? Is this coincidence or is there a reason why this happens?
Nissan - Maxima :: 2005 - Got P0420 Code
Keep getting the P0420 code on this vehicle. Have changed air filter, spark plugs, run fuel injector cleaner through the tank on Shell 93 octane fuel. Drove 430 highway miles to clean out the carbon and the SES light is still on and when we check the code it says Catalyst system effiency below threshold bank 1. How do i get this fixed?
View 1 RepliesToyota - Tacoma :: OBD2 Gives Same Code Twice - P0420?
My Toyota Tacoma is reporting (via an affordable OBD-II scanner) the same P0420 code: First as a regular code, then as a pending code. What could that mean?
View 6 RepliesGTI 337/20th Anniversary :: CEL Came On After DV Switch Replaced - Code P0420
So I recently (within the last month) replaced my DV for a Forge 007 and my stock air box for an EVOMS v-flow. My cel came on after the DV switch and was throwing the P0420 code at me. Then I swapped the intake and it has been good but I felt like I was running a bit rich and pulled my codes and it now has P0030 in addition to P0420. Why this is? I have 88K miles. Spoke to a mechanic and he says he thinks it is my cat dying. I'm a bit confused since I have a turbo back exhaust.
View 6 Replies