Clogging % not related to soot loading ?

[fixitsan]

Hello, I have FES and wonder what the variable 'clogging %' relates to ?

It might seem straightforward, but, clogging % for my 1.9 JTDm 16v seems to rise at roughly 5.1% per hour, regardless of how the car is used. I have confirmed with another owner in a different part of the country who is a member of the Alfa owner forums too, and his clogging % rises at about 5.1% also


How can this be ?

I have made a graph (apologies it uses AlfaOBD at this point, it was just easier this time) but FES reports identical information too so it's still valid

http://www.flickr.com/photos/28496053@N ... otostream/


I have a lot of graphs of this behaviour, covering hours of monitoring


This clogging % variable seems to just be behaving like a countup timer. I graphed everything from 22% to to 42%, and it makes no difference how I drive, or if the engine has just started from cold, the clogging % value continues to slowly increment at this preset and unchanging rate.


I am curious because i am experimenting with modifying my dpf and expected to see some changes t clogging...and then I saw no difference in behaviour.

Does anybody know the EDC16C39 regeneration methodology, the offical and complete methodolgy ?

Thanks,
Chris

[fixitsan]

A quick update to share some more data

I performed a 'replace particulate filter' routine and as expected the clogging % came down to 0

I've just had my first regen since then, at 84.5% (690km travelled). After regen the clogging fell to 12%

My dpf has several holes drilled through it. Before I drilled the differential pressure sensor was way high, because it was very badly blocked.

My pressure readings are on a par with a standard car that has a healthy dpf. Obviously mine won't clog up again, and I can live with the pointless regens. I just wonder what the dpf regen methodology is, or where I can find more specific information about it...is it in a Fiat or Bosch manual (have EDC16C39-CF4)


Chris

[yani]

Well, you've definitely done a great research on this subject. I also follow your thread in alfaowner...
Unfortunately, we cannot find this kind of information in any manual. Probably the only person who can give a genuine explanation on this topic is a programmer from Bosch or Fiat who has access to the source code of EDC16C39 software. I don't think we can find such person on the forums...

[fixitsan]

Thanks for that Yani.

I didn't think it would be common knowledge really but you never know. sometimes....

Cheers,
Chris