Need help with a fault code

[LY7Y]

Hey guys,
on my way back from Calgary to Edmonton my "Check Engine" light came on.
Hooked up the Laptop today and this is what VAGCOM splits out :

16085 - Warm up Catalyst Bank 1 : Efficiency Below Threshold
P0421 - 35-00--

Any Idea what it means ?

Car runs fine, no issues at all

Cheers
Frank

[2.7taudi]

Hey guys,
on my way back from Calgary to Edmonton my "Check Engine" light came on.
Hooked up the Laptop today and this is what VAGCOM splits out :

16085 - Warm up Catalyst Bank 1 : Efficiency Below Threshold
P0421 - 35-00--

Any Idea what it means ?

Car runs fine, no issues at all

Cheers
Frank

you need a new catalytic converter in bank one. is this the 3.0?

[LY7Y]

No, 2.7T
Is it better to replace both sides ?

[audifirst]

erase it, and check if it will come bank,
Call Audi Canada, the emission warranty has been extended to 12 years and can't recall the mileage , you might get free replacement

[LY7Y]

Good to know. I erased it and I will see if it comes back.
Will call Audi Canada on Monday and we will see what they said.

Thank you

[2.7taudi]

Good to know. I erased it and I will see if it comes back.
Will call Audi Canada on Monday and we will see what they said.

Thank you

i would not replace the one that doesnt need cats. cats are very expensive about 900 here in US not to mention the labor. it maybe possible the other one is on its way out since one is going but until the MIL turns on dont worry about the other one.

with the code erased drive it around for 200 miles and scan it again. my 2.8 threw the same code and after i erased it about 300 miles later it threw a code for an O2 sensor.

also im sure there is a software update related to the code you are getting. call the dealership and ask for software update for your car.

here in us the cat warranty is 8 years 80k miles.

[LY7Y]

So, went to my local Audi stealer and had a chat.
The extended warranty is only for a few cars and engine types, of course not mine.
My had a 8 years or 120.000 km which is expired.
You're right "2.7TAudi"
He estimate for changing the CC $1100 in parts + 5 hrs labor.
He advised to change the O2 sensors as well , this comes on top on the
estimate.
I'm looking for approx. $2500. Nice

Cheers
Frank

[2.7taudi]

So, went to my local Audi stealer and had a chat.
The extended warranty is only for a few cars and engine types, of course not mine.
My had a 8 years or 120.000 km which is expired.
You're right "2.7TAudi"
He estimate for changing the CC $1100 in parts + 5 hrs labor.
He advised to change the O2 sensors as well , this comes on top on the
estimate.
I'm looking for approx. $2500. Nice

Cheers
Frank

did you talk to them about a software update that is available for the 2.7 and 2.8 engine?

you can also talk to VAST performance who reroute the ecu to void the codes of cat codes and 02 sensors. so you will never have to worry about a check engine from cats again. and its only 2-3 hundred dollars.

2500 is quite a lot of damage. if you know any audi specialist they should be able to do the job for 300. the part is cheaper at geniuneaudiparts.com i believe its around 900 there for the SAME PART MADE BY AUDI.


also you dont really need to change the 02 sensors if they are not faulty. they cost about 200 a piece and you need 4.

ALSO once you take the cat out Save it. you might be able to get 50-100 dollars for them because they contain precious metals like platinum at a junkyard
good luck

[LY7Y]

The car was at the dealer in 2010 and they did everything incl. software. Ask him about it.
The price are Audi prices and I'm not going to pay it.
We have a pretty good shop here in town and I will ask him in a few days.
I don't get any codes from the O2 sensors so I'm not going to replace them.

[audifirst]

You can buy new cats for under $500 a piece and have shop install it for you, search ebay or kijji

[2.7taudi]

You can buy new cats for under $500 a piece and have shop install it for you, search ebay or kijji

ive read some posts where universal cats dont eliminate the MIL. wouldnt he be better off going oem?

[LY7Y]

"check Engine" went back on again
after only 100km. Guess she don't
Like it very much.

[audifirst]

ive read some posts where universal cats dont eliminate the MIL. wouldnt he be better off going oem?

I have aftermarket cats from Bosal for 5 years now without issues, another good company is DEC

[LY7Y]

I have aftermarket cats from Bosal for 5 years now without issues, another good company is DEC

Do you have a website for me to check it out ?

Thanks

[audifirst]

http://www.partsgeek.com/

[bigdadi]

First change all your sparkplugs, Iridium is about 60/set
Second a bottle a CRC cat cleaner in gas tank $15. You should find it in Advance Auto or Auto Zones. Worst case is buy it below.
http://www.amazon.com/CRC-05063-Guar...8417831&sr=8-1
Third check www.bigdaddiesgarage.com ... P0421 is the pax side post-cat O2 sensor. You need only 1 min-cat CEL eliminator $49.

You should not see that P0421 after that. If P0431 comes up (driver side) just do the #2, #3

Tech said the ECU spec is too narrow and actually the cat is still good. But the CEL is an eye sore, mini-cat should take care of it.

Use Top-tier gas : SHELL, MOBIL
http://www.toptiergas.com/

Chevron Canada
Esso
PetroCanada
Shell Canada
Sunoco Canada

[LY7Y]

First change all your sparkplugs, Iridium is about 60/set
Second a bottle a CRC cat cleaner in gas tank $15. You should find it in Advance Auto or Auto Zones. Worst case is buy it below.
http://www.amazon.com/CRC-05063-Guar...8417831&sr=8-1
Third check www.bigdaddiesgarage.com ... P0421 is the pax side post-cat O2 sensor. You need only 1 min-cat CEL eliminator $49.

You should not see that P0421 after that. If P0431 comes up (driver side) just do the #2, #3

Tech said the ECU spec is too narrow and actually the cat is still good. But the CEL is an eye sore, mini-cat should take care of it.

Use Top-tier gas : SHELL, MOBIL
http://www.toptiergas.com/

Chevron Canada
Esso
PetroCanada
Shell Canada
Sunoco Canada

Thank you very much.

Spark plugs are changed not even 1K ago and I only buy the expensive stuff (NGK Platinum).

If fill up only 94 at Husky and if is not
available, never lower than 91.

Tomorrow I will see if I get this emission cleaner stuff.
How long it will take until I know if it works ?
Do i have to burn a whole gas tank and
erase the code after that ?

Thank you again.

Frank

[bigdadi]

My friend did the reverse. He did the mini-cat CEL fix, then cleared the code, and it didn't come back ever since. After that he saw the CRC info, then add a bottle to the tank. The CRC's review in Amazon looks pretty good.

[LY7Y]

I decide to do the same.
Will call up these guys tomorrow
to order 2 of these mini cats.
It's the best way in my opinion.
Thanks again for your help

[LY7Y]

Oh, didn't pay attention for your user name, looks like its you, eh ?

[bigdadi]

Not related ... you only need one for the POST cat sensor in the passenger side (bank 1).

[LY7Y]

Contact bigdaddysgarage and they
said that the mini cat will not resolve
my problem.
He said I have to check the voltage
at the sensor and have to look for
corroded or frayed cable.
For what voltage I have to look for
if I test it ?
Where exactly is the sensor located?

question @bigdadi

Did this friend of yours get the same
false code that I got ?

Thanks
Frank

[bigdadi]

My friend got both P0421 (bank-1), P0431 (bank-2) at same time. Add 2 mini cat to post O2 sensors and done.

P0420 is same as P0421

[LY7Y]

Do you mean the sensors before
or behind the CC ?

[bigdadi]

The 2 senors after the CC ...their function is report data re the exhaust gas come from the CC, then the data is compared with the data of 2 sensors before the CC, thus it can tell if the CC is efficient enough ... as far as I know, the code is trigger once the CC efficiency goes down to 95%