[A4] How much for a catalytic converter for my A4?

furonobono at gmail.com furonobono at gmail.com
Thu Jan 24 07:38:19 PST 2008

Ok so let's see if I'm understanding this right from all the recent posts. Sorry to beat this subject to death everybody. 

Here's what I gather. The reason why my check engine light is going on and I'm having the intermittent power problems is because my cat converter is having issues. The reason why that is having issues is because I could have a faulty oxygen sensor that was contributing to the problem over time. So replacing just the o2 sensor won't necessairly fix my immediate power problems. It would just stop the blockage that's already there from getting worse. 

Am I understanding it correctly?

I don't want to invest in a new cat converter now only to have it die 20,000 miles later because I have a bad O2 sensor. Although it seems to me any decent mechanic would check that first...

Thanks all,

Sent via BlackBerry from T-Mobile

-----Original Message-----
From: "Aaron Jongbloedt" <jungle at hickorytech.net>

Date: Wed, 23 Jan 2008 23:54:39 
To:<a4 at audifans.com>
Subject: Re: [A4] How much for a catalytic converter for my A4?

A 2ndary O2 sensor will not cause any drivability issues.....it will throw a
check engine light, but that is the only thing you will notice.  The 2nd one
is ONLY for purposes of determining if your cat is functional.  The primary
one is for adjusting fuel mixture.

It still could be your cat...the guts of mine had come undone as a single
piece, and then jammed itself sideways down the cat a bit further.  I
unknowingly drove the car for a while that way...it steadily got worse....I
probably only knew something was up because my car is not stock and has a
boost gauge.... But yeah....by all means do get the codes and get a 2nd
opinion even if you have to pay $100 for diagnostic time. 

-----Original Message-----
From: a4-bounces at audifans.com [mailto:a4-bounces at audifans.com] On Behalf Of
Joyce Furono
Sent: Wednesday, January 23, 2008 11:34 PM
To: a4 at audifans.com
Subject: Re: [A4] How much for a catalytic converter for my A4?

I live in San Francisco, so drastic temperatures changes places like
Colorado has don't happen here. And the car lives indoors. I pay extra for

I've decided to first ask my mechanic for the codes and ask if he's thought
about my 2nd oxygen sensor being the culprit rather than a bad cat
converter. Then I can leave it as is and have a much cheaper repair.  As
Peter said, if it was completely blocked then I would have power problems
all the time. That makes sense to me. As it is I have no problems when I'm
driving on flat land whatsoever. When my car hits 140,000 miles, I'll be
much more open to getting a replacement...

However it makes me feel a little better knowing that Audi charges an arm
and a leg for the cat converter. He generally tries to get genuine parts
unless asked otherwise. He didn't say it was broken, or that he could hear
anything rattling around in there. He specifically said it was blocked.

Thanks for all the thoughts!
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