The previous owner 'fixed' the exhaust (too lazy to take the exhaust off the header flange?), see pictures.

I want to get it right. I assume there is a flanged part between the cats and the exhaust pipe flange (close to the motor). How is it called, where to get it, and how does it look like?

 

Ugh, seeing that makes me want to slap someone. Glad you're taking the time to fix it properly. Me thinks you're looking for flex pipes and/or the big *** sleeve clamps that go behind them.

That would be two of these:
http://www.ecstuning.com/Audi-B5_A4-...versal/ES3828/

And two of these:
http://www.ecstuning.com/Audi-B5_A4-...st/OEM/ES3205/

 

Should it then look something like this? Can't find pics of OEM exhaust:

 

I normally 'gut' the cats. Would the downstream O2 then need something like a "MIL" (a gizmo to trick the ECU to not through an error code with the cat gutted)? Or is it no as simple as that?

 

gutting the cats is fine as long as you don't have smog testing in your area. commonly, people use spark plug spacers on the O2 sensors to fool the ECU into not throwing a CEL

 

Can someone post a photo showing how the section is SUPPOSED to look?
The ad picture I posted shows a really small cat, while my car has what looks like much larger units (see photo)

Also, the ad pic shows a single piece including the cat. My car shows what looks like a 'ball' type flange connection before the cat (?) where the shitty weld is.

I need to put the car back together. Need input.

Thanks.

 

yes you need flex pipes right before the cat. you see the crap metal and JB where you have it now? all that is supposed to be a flex pipe welded in. the ball type flange you're talking about is part of the old flex pipe that probably rotted through and that's how the previous owner decided to fix it. i believe the size of the flex pipe you want a is a 4"x2.25". don't bother with the ECS flex pipes, they are junk

 

Yeah, we did that on the 1.8T when we installed the 'test' pipe. Put a
'non fouler' in which took care of that.

I will probably gut them while I am at it. At the very best, they don't do anything any more ('cleaning'). At the worst, they are getting plugged causing back pressure and problems.