On my 99 A6 2.8 Avant Quattro, I have a check engine light. Thecode reader get a code of PO432 -LEFT BANK. Is the left Cat bad or just an oxygen sensor.

Do you know of a good place to get a cheap CAT replacement and is it hard to fix (do you have to weld) ?

Please advise

 

There really is no cheap cat replacement for the A6. If you go stock the part alone will be close to $1800. I have the same problem and just ordered piggie pipes from Vast to fix the problem. Cost of the piggie pipe system was $700 and I may get some money back once I send back my old pipes. I am waiting on the shop to let me know when they can fit me in to get it installed. Once installed I'll let you know if it fixed the problem

 

Bazzag
Would the Vast piggie pipe work on an A6 02 manual quattro? The dealership is telling me that i need to replace both cats and it is going to cost me $3,200. The codes i have are P1127, P1557, P0421, P0431. I am wondering if it is just the O2 sensors, i have 98,000 miles.

 

A local Indy shop always changes the sensors before doing the cats because he would rather make an inexpensive mistake rather than an expensive one.

As for stock cats.. I did a 96 A6 cat for about $600 got the cat from force five in Concord NH 603-223-6700 and had it put on by an Indy shop. In this case I knew it was the cat because it plugged.

 

Could the problem just be a bad Oxygen sensor before i go and replace the CAT?

Please advise what the piggie pipe system is.

Also, I found a CAT on ECS tuning for $99 ( http://www.ecstuning.com/stage/edpd/...tegory=Exhaust) ,

Can i cut out the bad cat like a bad tooth and have this one weldedor clamed in? Where would thethe oxygen sensor go on a universal CAT?

 

here is the link for the piggie pipes. http://vastperformance.com/shop/prod...products_id=65

bslags: it should work as my A6 is manual too.

I was told last summer from the stealer I needed a new cat. CEL came back on around Dec. and noticed a more rough sounding engine. Got it checked out and bam again its the cat. I debated trading/selling itand getting a new car. Finally gave in and decided to keep it so just bought the part and got it yesterday.

 

The piggie pipe system shows it is for a 2.7T, not a 2.8.

Could the problem just be a bad Oxygen sensor before i go and replace the CAT?

Also, I found a CAT on ECS tuning for $99 ( http://www.ecstuning.com/stage/edpd/...tegory=Exhaust) ,

Can i cut out the bad cat like a bad tooth and have this one weldedor clamed in? Where would thethe oxygen sensor go on a universal CAT?

 

I would love to know the answer since I have the same problem...

 

Could the problem just be a bad Oxygen sensor before i go and replace the CAT? How much are Oxygen sensors and where is a good place to order one?

Please advise what the piggie pipe system is.

Also, I found a CAT on ECS tuning for $99 ( http://www.ecstuning.com/stage/edpd/...tegory=Exhaust) ,

Can i cut out the bad cat like a bad tooth and have this After market one weldedor clamed in? Where would thethe oxygen sensor go on a universal CAT?