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Audi A4 Fault query

bbability · 2008-04-14 19:31:50

Hi, Can someone tell me which oxygen sensor is that's faulty. I used Vag-com to find the fault and it has also been diagnosed with Bosch Esitronic software. Same fault found on both. 1 Fault Found: 16804 - Catalyst System: Bank 1: Efficiency Below Threshold P0420 - 007 - Short to Ground Is it the sensor on the manifold or…

14-04-2008 7:31pm

#1

bbability

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Posts: 1911

Hi,

Can someone tell me which oxygen sensor is that's faulty. I used Vag-com to find the fault and it has also been diagnosed with Bosch Esitronic software. Same fault found on both.

1 Fault Found:
16804 - Catalyst System: Bank 1: Efficiency Below Threshold
P0420 - 007 - Short to Ground

Is it the sensor on the manifold or the sensor on the other side of the cat??

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Comments

#2 14-04-2008 10:22pm

Timmaay

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Posts: 11335

It's saying that the Catalyst is at fault, so that would suggest that its the o2 sensor downstream of the cat. Search these forums for that code, those boys know their stuff.

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#3 15-04-2008 11:54am

Mr.Diagnostic

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Posts: 906

P0420 is set when the cat has failed the cat ageing test. Basically the cat is not as efficient as it should be. A magic "mechanic in a tin" cure could help but it is likely that it needs to be replaced.
P0420 does not point to either lambda sensor being faulty, quite the opposite.

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