Golf 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 :: 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
Ford F-150 - 1997-2003 :: Check Engine Light Came On - Error Code P0420
I was driving along today and my Check Engine light came on. I stopped at the nearest Advance Auto to have them pull the code and it came up with the P0420, Catalyst Efficiency Below Threshold (Bank 1). I asked what could cause this and they mentioned that the fuel that was put in could be causing it. They didn't mention any other possible causes. Any others? I'm thinking it could be the fuel because the last gas station that I stopped at and filled up at is one that I never go to, and maybe just got a bad batch of fuel.
View 14 RepliesFord Ranger / B-Series :: 1996 2.3L Automatic - Check Engine Light Came On / Error Code Is P0141
My 1996 Ranger runs ok but my check engine has come on. Using a scanner tool, indicates my cat monitor wont go to ready state and my error code is P0141. According to my research it indicates one of my 02 sensors. How to determine if its the one before or after the cat converter? About 6 months ago I had an exhaust leak repaired around my converter so I know I cant return it under warranty . If its the rear sensor , It looks fairly easy to replace but the front sensor looks a bit cramped.
View 6 RepliesGolf IV / Jetta IV :: 2003 - Error Code P0113 / Intake Air Temp Sensor
My 2003 Mk 4 Golf have had a lot of error codes and I have cleared most (O2 sensors, thermostat, and Mass Air Sensor) I now have an error P0113 which is the Intake Air temp Sensor.
So I need to clean the sensor first then maybe replace it, but I can't find the sensor on the intake manifold.
I have looked all through the U-Tube info, but nothing matches my 2003 Golf 2.0L ....
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 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 RepliesPrius (2004-09) :: 2005 - Error Code P0420 / CEL Came On Again?
Just picked up a 2005 with 146k and full Toyota service history, although seems a steering recall was not done. Will run it to the dealer today to check. I need to decide a.s.a.p. if I am keeping the car or not (I know the seller, he will take it back)
Anyway to cut a long story short, two questions.
1) Car had P3190 and P0420 when I got it. Seller reset, drove home and within 5 minutes on the road the CEL was back on. Checked the codes at home and see only a P0420. Much to worry about? Seems this might be big (Cat) or small (O2). Car getting great mileage - 60mpg at 60mph and it seems to be running great. Should I worry or forget about it? Note I am in Florida with no inspections.
Volvo - S40 :: 2001 - Getting Error Code P0128 And P0420?
So i've had this volvo for about 6 months now.I knew when I purchased it that the two codes being thrown were p0128-Engine coolant temperature, and p0420- Cat efficiency Bank 1.Inspecting mechanic said it needed a new cat to clear the p0420....I went ahead replaced the thermostat and changed the coolant to "fix" the p0128, and cleared the codes, I think the jiffy lube state inspector did not notice the that the catalytic converter test was Incomplete when he passed it. Lucky me I guess.
But now I know that I'll probably have to fix before it gets inspected again. Eventually the p0128 came back on, so I went and got a new ECT sensor. Still doesn't clear the p0128. What am i missing? Coolant temperature sits at a 3'oclock position pretty regularly and quickly. Where to start on the p0420 besides understanding its the Pre-cat o2 sensor that is throwing the code, is there anyway that these are related?
GTI 337/20th Anniversary :: 2002 - Way To Fix P0420 Error Code?
I have a 2002 GTI 337, 1.8T and I get the faulty code P0420 insuf.cat flow?? ... it is a way arround it
View 10 RepliesPrius (2004-09) :: 2005 - Pulled Over Error Code P0420
So I bought a used 2005 Prius back in August it had 88,000 miles on it and was out of warranty. But I had a full inspection on it and the car was in great shape. Well, after a few months of driving, I got the P0420 error. I took it into my mechanic who cleared the code and told me to call him if it came back on. It came back on, then I cleared it myself, and it came back on again. So it was confirmed that I had a bad catalytic converter.
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Golf IV / Jetta IV :: Got Error Code P0107?
So finally got past the smog cert issue and a bad map sensor in the intercooler. However, during the smog test, I was informed I am getting low air pressure in the intake! What causes this? A bad MAF? a leak? I have replaced the EGR, and all rubber that connects hard pipes. The only piece not changed out during the rebuild is the plastic flex line from the airfilter box to the turbo intake.
View 2 RepliesGolf IV / Jetta IV :: Code P0021 - Cam Timing Error
When checking my check engine light , I got P0021 a cam timing error, but my mk4 Gti runs perfectly ??
View 4 RepliesGolf IV / Jetta IV :: Error Code - Car Stuck In 3rd Gear
Damn car is stuck in 3rd gear! Hooked up scanner and the screen just says error! I have to keep the scanner in the vehicle, hooked up, just to drive the car. That's just so it'll shift as its supposed to! Now it's not letting me pull the code out, in order for me to erase it! It just keeps saying "error".
View 1 RepliesGolf IV / Jetta IV :: Keeps Dying - Error Code 16839?
I have a mk4 jetta 2.0l with about 130,000 miles. The issue with my car is that is has a rough idle and dies out completely when I put the car in neutral. I currently have codes 16839- EVAP system leak detected, 16487- Mass air flow sensor, 17978 - Engine start blocked by immobilizer, and 16795 - secondary air injection system incorrect flow detected. The secondary air pump was taken off the car before i bought it, so i do not think that code is responsible. Also all of my spark plugs and wires are new. I think the issue is either with my maf sensor or with a vacuum line. I have tried cleaner my maf and also unplugging it, and the car still has problem. Unfortunately i do not know where all of my vacuum line are. I have only checked the two the go into the sensor on towards the firewall. The one has vacuum, but the one coming for the egr valve did have any vaccum even when i tried with my other line on it. Im not sure if this is the issue, and if it would cause my car to die.
View 6 RepliesPassat (B5) :: CEL On With Error Codes P0036 And P0141
So I have my CEL light on error codes are P0036 & P0141.... how do I fix it??
View 1 RepliesGolf IV / Jetta IV :: Engine Light With Error Code P1296 Came On
I was cruising down the highway and my check engine light came on. I was a few minutes from a auto store and they said my code was p1296. I found out it is either the thermostat or the coolant temperature sensor. I wanna know where it is located in the engine bay. I have a 02 VW Jetta 1.8T.
View 1 Replies