# Help! Code P0430 Catalyst Eff. Below Threshold Bank 2.



## str8uplethal25 (Sep 17, 2007)

I just recently purcahsed a 2001 Audi A6 4.2L V8 with a Check Engine Light. My diagnostic code reader pulls up Code P0430 which is cat efficiency bank 2. Which Cat is Bank 2? Are these Cats connected to the manifold or something? How many Cats are on this car?


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## BlueSteW8 (Jan 27, 2008)

*Re: Help! Code P0430 Catalyst Eff. Below Threshold Bank 2. (str8uplethal25)*

I'm almost positive Bank 2 will be driver's side (US).
I would suggest trying the O2 sensor (downstream of the cat) first.
On the 30 valve V6, there are two catalytic convertors - one for each bank, and two O2 sensors per side. One each before, and after the convertors.
The 30valve V6 of that vintage (1999-2001) also had an overly sensitive thresh hold for cat errors.
There was a Technical Service Bulletin (TSB) for that.
It involved reflashing the ECU, which out of warranty was $100.00?
I have no idea if all, or any of this applies to the 4.2, but it might be worth checking into before paying big money for a new convertor, or two.


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## ilomax (Feb 28, 2007)

You cats are getting worn out. 
-If your car is under 70,000 miles, Audi will replace them for free.
-Got to an exhaust shop, get the two back cats replaced.
-Get the direct replacement from Audi (Big Money)
-Get the CEL Eliminators, pulls the o2 sensors away from the exhaust, so sensors get less exhaust, tricking the car to think that the cats are working fine.
If you got any questions PM me.


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