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Questions tagged [p0420]

An OBD11 fault code for Catalyst System Low Efficiency

0
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2answers
20 views

How many catalytic converters does a VW CC 2010 2.0L Sport have?

I have a P0420 code on my VW CC 2010 and I've narrowed it down to a faulty catalytic converter. I have edited this photo to try and explain easier. In the red circle is the catalytic converter I ...
3
votes
0answers
97 views

Nagging P0430 (and now a pending P0420 too!) 2004 Lexus ES330

I've got a 2004 ES330 (2nd owner) with roughly 315,000. We didn't pay much for the car in 2012 with 164,000 miles. So, i've never gone overboard in maintenance of it. A year ago, when it was time for ...
3
votes
0answers
820 views

P0420 Catalyst efficiency below threshold bank 1 With CO emission only!

I saw this code in OBD2 scanner on Skoda Fabia 1.2 2006 64hk petrol. It doesn't matter to me except that the car failed the inspection and I'm not allowed to drive it any more. The problem was too ...
3
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0answers
5k views

'05 Altima cranks, but will not start (sometimes)

Lately my 2005 Nissan Altima (3.5L) has been reluctant to start, having a 3-5 second delay from the time I turn the key and the starter begins working to the time the engine starts. Earlier today ...
2
votes
0answers
2k views

Affect of burning oil on O2 Sensors

I got a P0420 code and took my car to have a service and an investigate. I was told my car failed an emissions test and that is likely because the O2 sensors have failed causing a rich mix and higher ...
1
vote
0answers
19 views

Would a hole in the catalytic converter cause code p0420?

VW CC 2010. Catalytic converter was replaced when I first got the car at 78k miles. It is now at 83k miles. Downstream oxygen sensor was replaced at 80k miles. There is a small leak in the catalytic ...