I have been getting a CEL for a while, so I've had my mechanic check it out.

Initially it came back as 17511, O2 sensor(s), so he's replaced them both. They were apparently the originals, and the car is now at 165K . . .

Now that the sensors are operating properly he's getting code 16804, catalytic converter. Essentially, the second problem wasn't revealed until the primary issue had been dealt with.

I know the OEM cat from Audi is ridiculously priced, so he's told me about the after-market options. As I understand it, the cheaper ones have less precious metal in them, and therefore, they do not last as long.

Does anyone have a recommendation of a bolt-in cat that will offer longevity near or equal to the OEM piece?

I still like the car, and I figure it would be tougher to replace it than to bring it up to snuff with a bit of maintenance . . .

 

It's not that they don't last as long, they just don't 'filter' as much as OEM. Any aftermarket cat that's not some bargain-bin ebay junk will work well enough to keep the CEL off, if that's what you need. Remember that you get what you pay for, there's no such thing as a cheap cat that works well since 90% of the cost is in the catalyst material. Good time to get a HFC if you're planning on mods in the future.

 

He is extremely knowledgeable, and eminently trust-worthy, so I'll rely on his expertise as to the part's supplier.

Because I am a 'mature' driver I have no need for modifications - I can get into all the trouble I can handle with the car the way it came from Ingolstadt.

In any event, I have worked in the highest levels of motor racing as a journalist, so going fast on the street holds very limited appeal . . .