Hi,
First of all I'm new to the forums, just got a 99.5 2.8Q A a couple days ago with new timing belt and 114k for 6 grand.

My mechanic said that I needed 2 new Cats. He hooked it up to the computer and said that he got error codes for both catalityc converters. Like Catalytic bank 1 etc. bank 2 etc. I'm going to ask him tomorrow what the exact codes were b/c I'm hoping that perhaps the O2 sensors or something cheaper is bad.

The reason I think that he could be wrong is because I took the car to emissions here in Illinois today, expecting it to fail so we could show it
to the guy I bought the car from b/c I told him that the sale was dependent upon approval from my mechanic who quoted 2500 to replace both cats.
Well at emissions all they did was hook a computer up to it for a few seconds and I passed... wtf? If my mechanic hooked up to the car and read
that both cats were bad, wouldn't the emissions people catch this? Bad catalytic converters would be the number one thing the emissions people check.

Is it possible that something else is wrong that's causing the codes? I realize this is pretty useless without the codes, i'll get them tomorrow, but he said it was something
like "Bank 1 Cat" and "Bank 2 Cat".

If the Cats are bad, can I replace them myself? I have a lift in my garage to get underneath but the bolts look like they're pretty inaccessible.

What else can I do besides replacing both cats with oem cats that will still let me pass emissions?

Thanks in advance.

EDIT: CODES 16806 Bank 1 Catalytic Converter effeciency below threshold
16816 Bank 2 Catalytic Converter effeciency below threshold

 

if your mechanic cleared the codes for the bad cats before you went to inspection you could pass when they hooked the computer up because the fault code would be gone. If your cats aren't completely fried they do function, just not as efficiently as they should, which throws a code after a while of driving. however, just replacing the 02 sensors is probably not a great idea. if your cats are truly gone, and you just replace your 02 sensors, in the end you'll have to replace the cats anyway, and possibly have to replace the 02 sensors again, depending on how bad the cats are. the other thing is, why are your cats gone? I mean, thats a reasonably new car, so unless it was misfiring at some point your cats should be fine. either way I'd make the guy you bought the car from pay for the new cats.

if you have a lift you should be able to replace the cats yourself. and if you need to pass emissions i think the only thing you could do other than stock would be to put in some high flow cats. anyway, good luck either way.

 

codes required ( if I told you to crash into a wall and it would fix your car ) would you?? chances of both cats going is very rare and normally the bank 1 side goes first due to heat shock which is difficult to explain but ill try anyway, heat shock happens when your car goes through a cold puddle of water and the O2 sensor is exposed to extreme cold which sends a code to the ECU and note the CEL doesnt come on or it does for a very short time, that's why the codes are important

 

and I really do mean very very very rare for both cats and O2 sensors to go down at the same time

 

Opening post edited, codes posted.

 

While I'm looking up the codes, you should be able to get quality aftermarket direct fit converters for about 200 each. You can get universal cats for about 80 dollars each.

Check the functionality of the oxygen sensors.

 

Yeah but I'm a 2.8 so I'll have to weld them on, which I can't do. Would a repair guy weld them on or is there some law that they need to repair that stuff with oem.

 

there is a law that says that cats cannot be replaced with aftermarket cats unless the car is 7 years old, (it might b 6).

i have the same code on my 1.8, and im pretty sure its because of the chip thats throwing extra gas through them, causing them to fail faster.

i have a 98.

audi has high standards for thier emissions, its one of the things you pay for when u drop the coin for an audi. so when the code gets thrown, it is because it is below audi standards, not the state of illinois standards.

 

Here is a very inexpensive alternative:

 

Just replace them with straightpipes. If you just passed emissions, don't you have like a year or two before you have to worry about it again? **** emissions laws...