# 3.0l p0421 & p0431 fix



## 4ringkings (Oct 28, 2011)

After running into a bunch of faulty 3.0L catalytic converters on Audi B6 and C5 platforms, I realized the prices on the cats where super expensive and usually fail after another 80K to 100K of driving. I thought about a permanent, cost effective solution.

So we started to make test pipes for our customers and the results have been awesome.

3.0L "test" downpipes


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