Pages: [1]
Author Topic: C5 A6 4.2L Post cat O2 tune  (Read 4362 times)
airflite40
Newbie
*

Karma: +0/-0
Offline Offline

Posts: 2


« on: May 27, 2014, 09:11:33 AM »

Hi all,

I'm a new member, still learning still reading the great wealth of information on this forum and the associated pages.

I have a 2000 A6, with a 4.2L auto engine. Here's the situation that has brought me here:

A couple years ago the pass side cat went bad, and I replaced it with a OEM fit cat purchased online. Everything is great, the car passes emissions with no problems EXCEPT every few days I get P0422 cat below efficiency code that I have to clear and after many hours of research and reading online, the problem is the cat is a good cat, it just doesn't clean the exhaust to the standards set by the ECU that were artificially elevated from the factory.
There is a Techinal Service Bulletin for my model that reflashes the ECU to correct this and lower the efficiency standards but every dealer I have called about having it done is telling me it's gonna be a minimum of 2 hours labor to search and do the flash, which around here is more $ that I paid for the cat.

I've downloaded nefmoto and I have a blue ebay ODB cable and also have a VCDS cable, so if someone can help me with some guidance on how to read my ECU, change what needs to be changed so that I don't keep getting the P0422 code I would greatly appreciate it!

Thank you in advance.
Logged
sweegie
Full Member
***

Karma: +10/-2
Offline Offline

Posts: 137


« Reply #1 on: May 27, 2014, 03:00:29 PM »

Hi,

I have some experience with the C5 platform... I can't read my ECU with the Nefmoto software, but you may have better luck. An MPPS cable will work well with this ECU if Nefmoto fails.

Easiest way to solve your problem is to disable Cat diagnosis in your current flash, then upload back to the car. Happy to help if you can post the file.

Cheers
Logged
ddillenger
Hero Member
*****

Karma: +641/-21
Offline Offline

Posts: 5640


« Reply #2 on: May 27, 2014, 03:14:31 PM »

Hi,

I have some experience with the C5 platform... I can't read my ECU with the Nefmoto software, but you may have better luck. An MPPS cable will work well with this ECU if Nefmoto fails.

Easiest way to solve your problem is to disable Cat diagnosis in your current flash, then upload back to the car. Happy to help if you can post the file.

Cheers

You can read. The trick is to connect, attempt a read, allow it to fail, then reconnect. Try with 38k baud, and it should work the second time.

OP: memory layout is 29F800BB.
Logged

Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience!

Email/Google chat:
DDillenger84(at)gmail(dot)com

Email>PM
airflite40
Newbie
*

Karma: +0/-0
Offline Offline

Posts: 2


« Reply #3 on: May 28, 2014, 08:26:13 AM »

Thank you both! I will try to read and post the file tonight. I was going to try the 29F800BB layout since most A4/A6 use that one.
Logged
ddillenger
Hero Member
*****

Karma: +641/-21
Offline Offline

Posts: 5640


« Reply #4 on: May 28, 2014, 10:43:37 AM »

This is your original file.

BTW-saw the car on ebay. Love whitel
Logged

Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience!

Email/Google chat:
DDillenger84(at)gmail(dot)com

Email>PM
robin
Full Member
***

Karma: +20/-1
Offline Offline

Posts: 139


« Reply #5 on: June 11, 2014, 04:46:27 AM »

Looks to me like you'll want to set the byte at 01819A to 00 from 01. That should take care of both the bank 1 and bank 2 catalyst below threshold routines.
Logged
Pages: [1]
  Print  
 
Jump to:  

Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Page created in 0.015 seconds with 16 queries. (Pretty URLs adds 0s, 0q)