P0421 / P0431 Trouble Codes (Catalytic Converter) ... anyone have good fix? | Page 10 | FerrariChat

P0421 / P0431 Trouble Codes (Catalytic Converter) ... anyone have good fix?

Discussion in '360/430' started by bisel, May 25, 2017.

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  1. Skippr1999

    Skippr1999 F1 Rookie
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    Big congrats! Persistence wins. FYI, the product isn’t currently available on Amazon
     
  2. bisel

    bisel Formula 3
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  3. whatheheck

    whatheheck F1 Rookie
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    Outstanding news Steve!

    And thanks for sharing great knowledge and experience.

    Dan
     
  4. 360trev

    360trev F1 Rookie
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    Just a quick update.

    I've been working with AV Engineering today and we reflashed a customers F430 who had gone in for cat deletion. The thing is it had the Cat Efficiency CELs illuminated on both banks...

    P0430 and P0420.

    After a little bit of black magic I supplied a patched firmware using my SAK tool. First try around and no CELs. Great news

    So they are doing a more extensive test drives tonight to validate it stays off but I'm pretty confident it's done..

    So this feature is in beta now, working pending a few more tests...

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  5. chnco

    chnco Formula Junior

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    Trev-

    Can I take you up on the offer for a ‘99 no pre-car ECU? Shot you a DM!

     
  6. 360trev

    360trev F1 Rookie
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    Didn't get your message, I've pm'd you
     
  7. chnco

    chnco Formula Junior

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    My DM must not be going through, can you shoot me your email address?
     
  8. 360trev

    360trev F1 Rookie
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    Replied
     
  9. Mimmo Blue

    Mimmo Blue Formula Junior

    Apr 17, 2018
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    I know this thread is about error codes PO421 and PO431.
    I just put fabspeed headers on my 2001 360 and got it on the road yesterday. On my car I also installed 2 new primary O2 sensors since one of them refused to be removed from my original factory headers.
    I am now getting fault PO431 and PO432. Are these codes the same as what is being discussed in this thread? I downloaded a list of fault codes but did not see the PO421 and PO431 mentioned in this thread on the list.
     
  10. bisel

    bisel Formula 3
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    I believe P0431 / P0432 are codes indicating catalytic converter below efficiency. When you installed the Fabspeed headers, you removed some catalytic material in the stock headers. The downstream O2 sensor installed in the Ferrari's cats is measuring the exhaust gas, but since there is less catalytic material between the headers and the location of the downstream sensors, the car is throwing those two codes (one for each bank). You might get P0421 or P0431, etc. The reason is same.

    The solution (maybe) is to try one of a couple of options.
    1. Install a mini cat in the bung hole of the cats and thread the downstream sensor into the min cat.
    2. Install an O2 extender in the bung hole and thread the downstream sensor into that.
    This pulls the downstream O2 sensor out of the main exhaust gas flow and, in the case of the mini-cat solution, puts some catalytic material back in front of the O2 sensor.

    There is another problem (ask me how I know) and that is that by pulling the O2 sensor out of the exhaust gas flow, another code may rear its ugly head ... P0139 / P0159 ... O2 Sensor Circuit Slow Response time. Besides sensing a difference in the chemistry of the exhaust gas, the rear O2 sensor also wants to have a response time within a set time parameter of the front O2 sensor. Complicated, is it not?

    Take a look at post #217 ... https://www.ferrarichat.com/forum/threads/p0421-p0431-trouble-codes-catalytic-converter-anyone-have-good-fix.552866/page-22

    Now, if all else fails, you can try one of these two things:
    1. Get an ECU tune to ignore the downstream O2 sensor. This will not hurt anything as the downstream O2 sensors are there only to monitor the condition of the catalytic converter. It has nothing to do with fuel trim or any other engine parameter.
    2. Get a shop to cut a hole in the catalytic converter. Plug the the original bung hole and install the rear O2 sensor without an extender or mini-cat in the new bung hole.
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    Option #2 (install new bung hole) will modify the 360 catalytic converter to more like the F430 catalytic converter ... placing the rear O2 further downstream in the exhaust flow and the exhaust gases will have passed through more catalyst material and not relying on the material that was lost when you put in the Fabspeed headers.

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    Steve
     
  11. Mimmo Blue

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    Hi Steve, How have your adjustable O2 extenders been holding up. Still successful?
     
  12. 360trev

    360trev F1 Rookie
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    I've now successfully and fully tested / verified my SAK tool (Ferrari Swiss Army Knife) to 100% guarantee it fully to deactivate the Catalytic Converter efficiency CELs on all 360s and F430s. Never any chance of them to come back due to a drive cycle in 200 miles time...

    My solution is absolute since it actually removes the diagnostic check entirely. It will never produce a CEL for these codes anymore. You can run decat and even unplug the secondary o2s and fit bungs.

    Search for Ferrari Swiss Army Knife. Yes it says 360 in the thread but it now also supports F430s too..

    Trev
     
  13. mike32

    mike32 F1 Veteran

    May 13, 2016
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    I have the Capristo manifolds with no pre cats, yet i do not get the error messages very ofter, twice a year at most. I make a point of starting it and keeping my foot off the throttle until it warms up, avoiding sending fuel slugs up the pipe onto cold exhaust sensors, if the sensor is hot it does not drown in liquid fuel and throw a code. Works fine for me with no extenders trying to fool the system
     
  14. 360trev

    360trev F1 Rookie
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    #239 360trev, Aug 7, 2019
    Last edited: Aug 7, 2019
    There are still scenarios where you still get CELs. I'll see if I can document it fully it's overly complex and even depends on o2 aging...

    Also if your still running on stock maps with a sports exhaust (especially plus sports cats) your wasting your investment. If you drive back to back from stock mapping to even factory sports exhaust maps, let alone Stradale firmware, it's night and day different, I'm not even talking about tuning, its about having correctly calibrated maps for a sports exhaust the way factory intended. You'd swear your driving a different car. Smoother, better idle, no flat spots or snatchiness.

    We've all been fitting sports cats and exhausts for years without realizing it was badly messing with the drivability because we never had the factory sports exhaust ecus. Most people thought it was just for different exhaust valve opening times. They are not, they dramatically improve drivability and power too. They are quite differently mapped.
     
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  15. 360trev

    360trev F1 Rookie
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    Forgot to mention there are big differences in EU programming and US firmware. US is more strict at issuing CELs and the newer the car and thus stricter emissions the easier it is to trigger..
     
  16. Mimmo Blue

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    I still don't see an answer to my question. Is there a difference between the codes I am getting which are P0422 and P0432 and the title of this thread which is P0421 and P0431? The description seems the same.
     
  17. 360trev

    360trev F1 Rookie
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    Its entirely to do with where your car came from. If you have a US spec car you get different error codes to EU cars and it varies between model years too. Hence the reason why I offered to dump the P-Codes table for a given car ECU firmware dump. You give me the numbers from the ecu label and I tell you exactly what codes are in there and what are enabled or not. As you can see below


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    I can just reflash them with the cat efficiency protection disabled. Job done. Never see these pesky codes again and you can dodge paying $1,000 bill just for the pair of cat ecus alone..
     
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  18. G. Pepper

    G. Pepper Three Time F1 World Champ
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    Trev, would it be a good idea to get a pair of the ECU's from a salvage car so the turnaround won't keep my car off the road for an extended period?
     
  19. 360trev

    360trev F1 Rookie
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    Not really much point.

    Its ofcourse nice to have a spare ecu so you have no down time if one fails... Which is possible to do when I remove the security pairing and you reflash the spare with your own firmware.

    Its only a 1 day turn around. I have affiliates in Texas so you may even be able to do a while you wait service!
     
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  20. Mimmo Blue

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    Ok now I understand. Thank you
     
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  21. ridege55

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  22. bisel

    bisel Formula 3
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    Hmm. If you went that long before getting the codes, perhaps the easiest thing to do is merely clear the codes and see it they return. Clearing codes every year or two is not a big deal, IMO.

    Best of luck.

    Steve
     
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  23. ridege55

    ridege55 Formula 3
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    Thanks Steve. Seems like a good idea. I will probably clear them tonight and go for a long drive over the weekend.
     
  24. 360trev

    360trev F1 Rookie
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    ... Or in countries which allow it you can just pm me for a permanent software solution/fix to this mess. An engine ecu reflash with cat efficiency checking deactivated inside the firmware. Guaranteed to never get these pesky CELs again ever and no need to have secondary o2s even plugged in. They are turned off as only used to monitor cat efficiency on 360s.

    Also I recommend deactivating cat ecu system checking too as it has a terrible failure rate and if you have a sports exhaust it's a must to use either factory sports exhaust calibration maps as these get rid of horrible flat spots in the rev range that come with a sports exhaust fitment.

    Better still I can offer an upgrade to Challenge Stradale spec firmware which I've perfected and fully tested on all 360 models and yes this even works 100% for the Modena/Spider spec cars, any model year including gated and f1 cars. Check out the Ferrari Swiss Army Knife thread. This now works 100% on F430s too and currently in testing for other models.
     
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  25. wbt

    wbt Karting

    Nov 28, 2014
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    Trev - I've improved upon the factory cat temperature ecu design to something much more reliable and modern using some good quality analog devices chipsets with far higher common mode noise rejection than the rudimentary vescovini factory effort. My testing showed that the factory cat ECU can drift and also move about under high EMC environments, which likely accounts for the regular intermittent "slow down" false alarms many 90's to early 2000's era owners experience. I think it's worth keeping cat temp monitoring to A) protect the cats in event of raw fuel entering the exhaust stream as damage happens very quickly and B) preventing red hot cats causing some fairly catastrophic secondary damage or worst case a fire. The fact my new cat ECU can restore faith in the system that a slow down light indicates a real warning should offer peace of mind. Coupled with a reflash from your SAK tool these annoying exhaust issues can not only be solved, but the cars performance hugely improved (you will be getting my engine ECU's to reflash once I have some downtime too).
     
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