Jump to content

Server Lease Renewal/Software Licenses

Our yearly server lease, software licenses, as well as hardware operating costs, ARE due Dec 6th, 2021. Our current donations have fallen far short of the funds we need to renew. Please remember the RennTech.org community is Member supported so please consider a donation to help...  THANK YOU!

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Can Someone Help Me Interpret My Durametric O2 / Cat Data Please?


Recommended Posts

Hey all,

 

So I'm trying to track down a 2 code CEL that my 04 has thrown, they are PO421 & P0431.  I know these are Cat codes but since it could also be something else (bad 02, etc) I decided to record some live data to look at.  I'm very new to Durametric and used it to capture the below values and exported it to an excel file.  It is about 2.5 minutes worth of data and I wasn't sure exactly what to select in Durametric so I tried to get what I thought was appropriate to diagnose what to replace.  The Values I selected were:

 

 

1.  Exhaust Temp Ahead & After CAT

2.  O2 Sensor Voltage Downstream Bank 1 & 2

3.  Status of Catalyst Bank 1 & 2

 

I may be putting too much emphasis on temps, but based on the inlet/outlet temps of the CAT, I'm wondering if that is showing me the answer?  At the beginning the inlet temp was lower but not by a ton, then midway through till the end the outlet temps were lower which I think is a sign the cat is not working correctly.  I think the O2 readings appear ok since they don't jump around to much and stay around the .5V figure with mainly .6-.7 being the most common in the data stream which is where downstream O2's should be correct?  I have no idea what the Status of Catalyst is and was hoping someone could clue me in.  I selected it b/c I "thought" it might be important but the value is solid throughout not sure if that is good or bad or what or if it even tells anything.

 

I'm trying to plan my course of action which I've game planned to a few different things depending on what the data tells me:

 

1.  Maybe the CATS can revived with a chemical cleaner (doubtful).  I know that these codes will throw if the cats operate at less than 95% efficiency, so maybe mine is only slightly below that and can be cleaned a bit, but the temperature data difference at the inlet vs outlet is making me think this might be a waste?

 

2.  New O2 sensors.  These aren't too expensive but I hate just throwing new parts at something without something to back it up.  From the data stream it didn't look like they were too out of wack but maybe I'm missing something, I've certianly replaced them in other cars when I was having CAT codes and that corrected the problem so...dunno.

 

3.  New CATS.  I've found some reasonably priced aftermarket OEM fit/finish replacements from a company but hate to get into that if any of the easier stuff might work.

 

4.  Go all ghetto and put an anti-fouler in the downstream O2's to get the light off (last resort).

 

The car runs great and getting around 18 mpg in mostly city/some hwy, so that seems normal.  Just need some advice for those of you that know Durametric and can help a member out by looking at the excel data file.  If I missed some important data that I needed to log please tell me and I'd be happy to go data log whatever you all think I need to, again I'm new to Durametric and there are so many options I was a little overwhelmed and went with my "gut" feeling.  Anyway thanks for any help, here is the exported data from Durametric:

 

2004_Cayenne_Durametric_Export

Edited by cfiiman
Link to comment
Share on other sites

  • Moderators

Hey all,

 

So I'm trying to track down a 2 code CEL that my 04 has thrown, they are PO421 & P0431.  I know these are Cat codes but since it could also be something else (bad 02, etc) I decided to record some live data to look at.  I'm very new to Durametric and used it to capture the below values and exported it to an excel file.  It is about 2.5 minutes worth of data and I wasn't sure exactly what to select in Durametric so I tried to get what I thought was appropriate to diagnose what to replace.  The Values I selected were:

 

 

1.  Exhaust Temp Ahead & After CAT

2.  O2 Sensor Voltage Downstream Bank 1 & 2

3.  Status of Catalyst Bank 1 & 2

 

I may be putting too much emphasis on temps, but based on the inlet/outlet temps of the CAT, I'm wondering if that is showing me the answer?  At the beginning the inlet temp was lower but not by a ton, then midway through till the end the outlet temps were lower which I think is a sign the cat is not working correctly.  I think the O2 readings appear ok since they don't jump around to much and stay around the .5V figure with mainly .6-.7 being the most common in the data stream which is where downstream O2's should be correct?  I have no idea what the Status of Catalyst is and was hoping someone could clue me in.  I selected it b/c I "thought" it might be important but the value is solid throughout not sure if that is good or bad or what or if it even tells anything.

 

I'm trying to plan my course of action which I've game planned to a few different things depending on what the data tells me:

 

1.  Maybe the CATS can revived with a chemical cleaner (doubtful).  I know that these codes will throw if the cats operate at less than 95% efficiency, so maybe mine is only slightly below that and can be cleaned a bit, but the temperature data difference at the inlet vs outlet is making me think this might be a waste?

 

2.  New O2 sensors.  These aren't too expensive but I hate just throwing new parts at something without something to back it up.  From the data stream it didn't look like they were too out of wack but maybe I'm missing something, I've certianly replaced them in other cars when I was having CAT codes and that corrected the problem so...dunno.

 

3.  New CATS.  I've found some reasonably priced aftermarket OEM fit/finish replacements from a company but hate to get into that if any of the easier stuff might work.

 

4.  Go all ghetto and put an anti-fouler in the downstream O2's to get the light off (last resort).

 

The car runs great and getting around 18 mpg in mostly city/some hwy, so that seems normal.  Just need some advice for those of you that know Durametric and can help a member out by looking at the excel data file.  If I missed some important data that I needed to log please tell me and I'd be happy to go data log whatever you all think I need to, again I'm new to Durametric and there are so many options I was a little overwhelmed and went with my "gut" feeling.  Anyway thanks for any help, here is the exported data from Durametric:

 

2004_Cayenne_Durametric_Export

 

First of all, it is always helpful to provide the car's year and model in these inquiries.

 

Assuming it is a Cayenne:

 

P0421 Catalytic conversion, bank 1 – above limit value Possible cause of fault - Oxygen sensors in front of and behind catalytic converter are interchanged - Catalytic converter faulty .

 

P0431 Catalytic conversion, bank 2 – above limit value Possible cause of fault - Oxygen sensors in front of and behind catalytic converter are interchanged - Catalytic converter faulty.

 

A little light reading on the subject of O2 readings and state of the cats (from a Boxster diagnostics manual, but the technology is the same):

 

ThreewaycatandO2sensoragingdiagnostics_z  ThreewaycatandO2sensoragingdiagnostics2_

 

You need to go back to your Durametric system and pull up the graphical display of the before and after cat voltages to see if they are following each other; if they are, you need new cats.

Link to comment
Share on other sites

 

Hey all,

 

So I'm trying to track down a 2 code CEL that my 04 has thrown, they are PO421 & P0431.  I know these are Cat codes but since it could also be something else (bad 02, etc) I decided to record some live data to look at.  I'm very new to Durametric and used it to capture the below values and exported it to an excel file.  It is about 2.5 minutes worth of data and I wasn't sure exactly what to select in Durametric so I tried to get what I thought was appropriate to diagnose what to replace.  The Values I selected were:

 

 

1.  Exhaust Temp Ahead & After CAT

2.  O2 Sensor Voltage Downstream Bank 1 & 2

3.  Status of Catalyst Bank 1 & 2

 

I may be putting too much emphasis on temps, but based on the inlet/outlet temps of the CAT, I'm wondering if that is showing me the answer?  At the beginning the inlet temp was lower but not by a ton, then midway through till the end the outlet temps were lower which I think is a sign the cat is not working correctly.  I think the O2 readings appear ok since they don't jump around to much and stay around the .5V figure with mainly .6-.7 being the most common in the data stream which is where downstream O2's should be correct?  I have no idea what the Status of Catalyst is and was hoping someone could clue me in.  I selected it b/c I "thought" it might be important but the value is solid throughout not sure if that is good or bad or what or if it even tells anything.

 

I'm trying to plan my course of action which I've game planned to a few different things depending on what the data tells me:

 

1.  Maybe the CATS can revived with a chemical cleaner (doubtful).  I know that these codes will throw if the cats operate at less than 95% efficiency, so maybe mine is only slightly below that and can be cleaned a bit, but the temperature data difference at the inlet vs outlet is making me think this might be a waste?

 

2.  New O2 sensors.  These aren't too expensive but I hate just throwing new parts at something without something to back it up.  From the data stream it didn't look like they were too out of wack but maybe I'm missing something, I've certianly replaced them in other cars when I was having CAT codes and that corrected the problem so...dunno.

 

3.  New CATS.  I've found some reasonably priced aftermarket OEM fit/finish replacements from a company but hate to get into that if any of the easier stuff might work.

 

4.  Go all ghetto and put an anti-fouler in the downstream O2's to get the light off (last resort).

 

The car runs great and getting around 18 mpg in mostly city/some hwy, so that seems normal.  Just need some advice for those of you that know Durametric and can help a member out by looking at the excel data file.  If I missed some important data that I needed to log please tell me and I'd be happy to go data log whatever you all think I need to, again I'm new to Durametric and there are so many options I was a little overwhelmed and went with my "gut" feeling.  Anyway thanks for any help, here is the exported data from Durametric:

 

2004_Cayenne_Durametric_Export

 

First of all, it is always helpful to provide the car's year and model in these inquiries.

 

Assuming it is a Cayenne:

 

P0421 Catalytic conversion, bank 1 – above limit value Possible cause of fault - Oxygen sensors in front of and behind catalytic converter are interchanged - Catalytic converter faulty .

 

P0431 Catalytic conversion, bank 2 – above limit value Possible cause of fault - Oxygen sensors in front of and behind catalytic converter are interchanged - Catalytic converter faulty.

 

A little light reading on the subject of O2 readings and state of the cats (from a Boxster diagnostics manual, but the technology is the same):

 

threewaycatando2sensoragingdiagnostics_z  threewaycatando2sensoragingdiagnostics2_

 

You need to go back to your Durametric system and pull up the graphical display of the before and after cat voltages to see if they are following each other; if they are, you need new cats.

 

 

Thanks for the info, sorry it is a 2004 Base model, it says that on the excel file but people might miss it.  The problem is I don't think Durametric can do the upstream O2's unless I'm missing something, I can't find that selection to include in the analysis graphing, do you know for sure it is there?

Link to comment
Share on other sites

  • Moderators

 

 

Hey all,

 

So I'm trying to track down a 2 code CEL that my 04 has thrown, they are PO421 & P0431.  I know these are Cat codes but since it could also be something else (bad 02, etc) I decided to record some live data to look at.  I'm very new to Durametric and used it to capture the below values and exported it to an excel file.  It is about 2.5 minutes worth of data and I wasn't sure exactly what to select in Durametric so I tried to get what I thought was appropriate to diagnose what to replace.  The Values I selected were:

 

 

1.  Exhaust Temp Ahead & After CAT

2.  O2 Sensor Voltage Downstream Bank 1 & 2

3.  Status of Catalyst Bank 1 & 2

 

I may be putting too much emphasis on temps, but based on the inlet/outlet temps of the CAT, I'm wondering if that is showing me the answer?  At the beginning the inlet temp was lower but not by a ton, then midway through till the end the outlet temps were lower which I think is a sign the cat is not working correctly.  I think the O2 readings appear ok since they don't jump around to much and stay around the .5V figure with mainly .6-.7 being the most common in the data stream which is where downstream O2's should be correct?  I have no idea what the Status of Catalyst is and was hoping someone could clue me in.  I selected it b/c I "thought" it might be important but the value is solid throughout not sure if that is good or bad or what or if it even tells anything.

 

I'm trying to plan my course of action which I've game planned to a few different things depending on what the data tells me:

 

1.  Maybe the CATS can revived with a chemical cleaner (doubtful).  I know that these codes will throw if the cats operate at less than 95% efficiency, so maybe mine is only slightly below that and can be cleaned a bit, but the temperature data difference at the inlet vs outlet is making me think this might be a waste?

 

2.  New O2 sensors.  These aren't too expensive but I hate just throwing new parts at something without something to back it up.  From the data stream it didn't look like they were too out of wack but maybe I'm missing something, I've certianly replaced them in other cars when I was having CAT codes and that corrected the problem so...dunno.

 

3.  New CATS.  I've found some reasonably priced aftermarket OEM fit/finish replacements from a company but hate to get into that if any of the easier stuff might work.

 

4.  Go all ghetto and put an anti-fouler in the downstream O2's to get the light off (last resort).

 

The car runs great and getting around 18 mpg in mostly city/some hwy, so that seems normal.  Just need some advice for those of you that know Durametric and can help a member out by looking at the excel data file.  If I missed some important data that I needed to log please tell me and I'd be happy to go data log whatever you all think I need to, again I'm new to Durametric and there are so many options I was a little overwhelmed and went with my "gut" feeling.  Anyway thanks for any help, here is the exported data from Durametric:

 

2004_Cayenne_Durametric_Export

 

First of all, it is always helpful to provide the car's year and model in these inquiries.

 

Assuming it is a Cayenne:

 

P0421 Catalytic conversion, bank 1 – above limit value Possible cause of fault - Oxygen sensors in front of and behind catalytic converter are interchanged - Catalytic converter faulty .

 

P0431 Catalytic conversion, bank 2 – above limit value Possible cause of fault - Oxygen sensors in front of and behind catalytic converter are interchanged - Catalytic converter faulty.

 

A little light reading on the subject of O2 readings and state of the cats (from a Boxster diagnostics manual, but the technology is the same):

 

threewaycatando2sensoragingdiagnostics_z  threewaycatando2sensoragingdiagnostics2_

 

You need to go back to your Durametric system and pull up the graphical display of the before and after cat voltages to see if they are following each other; if they are, you need new cats.

 

 

Thanks for the info, sorry it is a 2004 Base model, it says that on the excel file but people might miss it.  The problem is I don't think Durametric can do the upstream O2's unless I'm missing something, I can't find that selection to include in the analysis graphing, do you know for sure it is there?

 

 

Positive, it should be in the actual values under the engine sections.  These curves were generated off a 996 with a bad cat on one side using the Durametric software:

 

mblso4.jpg

Link to comment
Share on other sites

  • 1 year later...
  • 1 month later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.