Slvrs6

Hey all,

I have a hole in one of my catalytic converters... getting a burly growl from it and need some replacement ideas.

Can I go with a generic? Magnaflow and have an exhaust shop weld it in?

What are my options here?

4Driver4

I doubt that you have a hole in one of your cats. It's probably a bad flex joint. Find a good exhaust shop to weld in a new one. This is a common repair.

nickcarguy

4 Driver 4: I was not aware a new flex joint could be welded in to save the cost of a complete new cat. That's just what I needed about a year ago. I went for almost $1300 bucks from an independant to replace my passenger side cat that was leaking from the flex joint. And the driver side one is in poor shape too.
I'm located in Northern NJ, and not aware of any decent muffler shops that could do this. Also, who sells the replacement flex joint?
Many thanks.

4Driver4

Any decent muffler shop stocks a wide variety of flex joints and they are available at most auto parts stores. Find a good local Audi shop (not the one the replaced your entire cat) and see if they can do it or if they can recommend someone.

nickcarguy

Thanks 4Driver. Wish I had know sooner. This is my '00 C5 Avant, with 110K miles. The car has been meticulously maintained, and is in superb condition. Lots of life left.
Can the flex joint be removed and re-welded without dropping the cat? is there sufficient clearance?

Donuts

Finding a good install place can be tough. You will need to call around and prices can vary greatly for a flex install...highest quote I got was $100 per side for my old ATQ B5 Passat. Ultimately, I had both of mine done by a Mom & Pop place for $100. No chain (Midas or Meineke) would touch it. I purchased the replacement flex from Exhaust Direct - http://www.exhaustdirect.ca/ ....call and talk to Jim Yanch.

Side note, I also purchased complete Cat assemblies from Jim for my AHA A6 after the driver's cat started to break apart internally, rattled and threw a 16816 code. I don't expect them to last as long as the OEM but at $190 per side and him standing behind the federal warranty it worked for me.

VONBOTTLE

both the flex joints on my downpipes were torn and had them both replaced (unfortunately about a month before i blew a turbo and ended up installing piggie pipes, so an unforseen waste of money). unfortunately, no one really stocks the oem size flex joint which is around 5" long, you can probably search and find one online i'd imagine, but even audi doesn't carry them - makes perfect sense to me...anyway, you'll have to weld in 4" flex joints and a filler piece of pipe, i think the flex sections were like $60 for both if i recall. there was like 4 hours labor to weld them in as they're difficult to weld in without removing the downpipes

4Driver4

Not usually. They cut the old joint out and cut the pipes to fit the new joint while the cat is in the car. Once the new joint is fitted and tack welded in place, they unbolt the cat but leave the O2 sensors plugged in. This allows them to swing the assembly down away from the body and trans to weld to properly.

The most time consuming part of the job is cutting out the old joint.

nickcarguy

ECS has a full range of universal flex joints on their site. But I just spoke with them and even they have no idea which one is correct for this application. They range from 2" to 2.5" in diameter. And 2" to 6" in length. The gentleman I spoke with said the only way to know for sure is to cut the old one out and measure it. Sounds absurd to me.
Does anyone know what the corrct diameter and lenth needs to be?
I undertand now whay my indie shop just put in a whole new cat..
Thanks all.

4Driver4

There is no "correct" one. This is art, not science. Let the shop that does the job supply the part. Finding the part is easy; the hard part is finding someone who can weld well and cares enough to do a decent job.