GTI 337/20th Anniversary :: Oxygen Sensor Code P0420 Will Randomly Come On In Any Weather
Jan 13, 2012
My Jetta has been throwing this code on and off for over a year now. It used to only come on when it was really cold with wet roads. Now the code will randomly come on in any weather. I usually just clear it but it's coming on to often now. I don't notice any performance issues or gas mileage problems.
Scan shows : Trouble Code - P0420 Catalyst System Efficiency Below Threshold (Bank 1)
I've been reading and apparently 1.8t engines only have One bank? I'm assuming this the the front 02 sensor throwing this but not sure?
I have an aftermarket exhaust/high flow cat. Apparently this can be caused by a high flow after market catalytic converter and one solution is to use a test pipe or spacer to move the rear O2 sensor further from the exhaust gas flow. But I'm not sure this is the issue since I think it's my front sensor throwing the code? That's not by the Cat is it? I just don't want to have the sensor replaced to have the code still come up.
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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...
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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.
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I have a 2002 GTI 337, 1.8T and I get the faulty code P0420 insuf.cat flow?? ... it is a way arround it
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I have an 04 GLI and keeps throwing a code for the 02 sensor, and after putting the car on the lift, and disconnecting the 02 sensor harness, a fine oil leaks out at the end of the connector and smells and looks like power steering fluid.
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I drive an 05 Gli n my car has been shutting off on me took it for a diagnostic n the code po322 came up engine speed sensor. So my question is. Is their a DIY on replacing the sensor I'm picking it up tomorrow. To be honest I don't even know where the sensor is located...
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I have a 2010 Toyota Corolla 1.8L, the base model.
I recently had a check engine light, VSC off light (blinking) and traction control light come on. I took it to Autozone and had a p0037 code ring up for a new Bank 1 Sensor 2 oxygen sensor (downstream). I believe I have found the correct sensor (located under car, approximately near drivers seat) and it looks simple to replace, aside from the fact that the wires go through the car body.
Can confirm that I have located the correct sensor? And if so, what is the best way to get to where the wires connect?
Is it located under the drivers seat? What should I do about the rubber grommet located under the car where the wires appear to pass through?
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The service truck threw a CEL, and i pulled oxygen sensor performance bank one sensor one code. That would be driver side sensor between the manifold and cat, rite? Don't want to change the wrong one...
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Just got hit with the P0130 code when my CEL came on for the pre-cat o2 sensor. On ecs there are front and rear sensors. I'm assuming front would correspond to the pre-cat that is throwing the code?
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I put in a new sensor to stop the problem but now I have the code 00778 which is steering angle sensor and then says 005 no or incorrect basic settings/adaption. I went through the Ross-Tech site to reset the code in group 60 and activate the basic settings, but I am then told that group 060 is not available. I have tried to set the steering wheel angle straight but the angle still says its at 349.47*. My car is a 2004 Jetta GLI 1.8T.
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Replaced my post cat drivers side O2 sensor tonight because I was getting zero voltage and a p0430 code. This is bank 2 sensor 1.
But I'm still reading zero voltage!! How could I still be getting zero voltage?? I checked the connections and they are firm. Checked every single fuse in car.
After my recent accident, the center console lights don't illuminate. My nav door doesn't close too. Could these all be related?? The connector for the O2 sensor is right next to the console, so maybe there is a loose connection or plug or perhaps a stray ground?? I do have wires all over the place in under the shifter bezel from aftermarket stuff..
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I received error code P0031 on my 06 Avalon the other day. It states that the HO2S (Heated Oxygen Sensor) is bad. Bank 1 Sensor 1. I located the sensor but have a few questions...
Just to give an over view for those that don't know where these are, there are 4 sensors the one in the front on the manifold (upper - B2, S1), (lower - B2, S2) and the rear manifold (upper - B1, S1), (lower - B1, S2).
All of the sensors look the same with 4 wires. what the part number is for the sensor? Also since this is the hardest one to get to, I would like to know where the wire routes to. I found the wire up to the connector on every other sensor except the one I need (B1S1). It looks like it runs towards the top of the engine but from the top I don't see it.
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I have a 2001 Exrursion 5.4L V8. The code P1131 comes up and it says "Lack of upstream heated oxygen sensor switch - sensor indicates lean - bank #1". I hear it could be the sensor that is bad or there is a vacuum leak. It runs like a champ, no spitting, no sputtering, no missing, no ruff idle. What do I need to do to fix it or where do I need to start looking?
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So I did a couple searches and found a couple MK3's with this issue however I did not find anything for the MK4.
The last couple days, we have been over 90 degrees in the afternoon. My black 03 20th 1.8t sits on the side of the road at work in the direct sun from 12:30 (lunch) until 5pm when I get off.
The last 2 days, when I have gone to start it, it cranks and cranks for 5-8 seconds before it starts to catch and finally stumbles to life. Once its running, everything feels fine. If I turn the car off and restart it, it starts fine.
In the mornings in the garage, evenings when its cooler or leaving for lunch before the day has gotten really hot, it starts fine. It only seems to be affected after sitting in the direct afternoon heat for a few hours.
I have read vapor lock, dying crank position sensor, ignition issues, starter etc. I am going to rule out the starter as the car cranks like normal. It simply does not fire.
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Ok so first of all my car started perfect everyday but i live in Boca Raton FL so it is normally very hot but the past few days it has gotten rather cold for FL like 30ish...So my question is...is it possible that my starter endured such extreme different weather changes that it ruined it or could it be that it has been too cold for the starter to work two nights ago it didnt work and also this morning but it started warming up again and it took a while seconds but it started but very bad??? could it be it just has to warm up again and it will be fine? or do i need a new starter..
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My car alarm keeps going off randomly. It doesn't matter if I lock it or not. The car alarm just goes off and quits on its own. What might be wrong?
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I just recently put a new battery in and I was wondering if thats why my car alarm goes off sometimes? I've also noticed about a week ago in my gauge cluster that the sign for the door being opened was on and then it turned off and then flicker on and off for about 30 sec ? So I think that has to do with the alarm but my question is how do I fix this problem???
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So my 20th randomly won't start. It's happens about once a week or so. Most of the time when it happens the car cranks but doesn't start. Every once in awhile when I turn the key nothing happens at all and I have to keep trying and it'll crank and turn on. I also have no way to check for codes
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So recently my car alarm on my GLI has been going off randomly while I'm at work and school. The alarm goes off for about 5 minutes and then stops. Tonight it's going off constantly and I don't want to wake up my neighbors and I need to sleep tonight. It's going off every 5 minutes even after I disarm the car. I've been searching up why it's going off online and haven't had any luck finding the source. Also after a few minutes of unlocking it the car locks itself and then the alarm sounds.
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2 or 3 months ago i had to get my fuel pump changed due to my car dying randomly on the free way multiple times a week. The problem disappeared after changing the fuel pump, however it has started happening again recently. The car wont completely die but while going 60 mph or more, the car will suddenly lose all power and the gas pedal doesn't do anything for a couple seconds, then all power comes back and i have control of the car again. Why this is happening?
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My engine light randomly popped up. Brought it to a shop, got scanned and cleared. A few days later, light came back on. From the scan, these two things popped up
17705 Pressure Drop between Turbo and Throttle Valve P1297
19537 Engine Temperature too Low P3081
cars a bmp 20th with 181km on it (around 111000 miles i think lol)
Also, how could i tell if my car has an aftermarket LSD, cause the PO claimed to have put in a quaife LSD. also, how could i tell if its chipped other than scanning it?
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