NefMoto

Technical => Tuning => Topic started by: prj on April 09, 2012, 04:55:08 PM



Title: Turning off catalyst heating
Post by: prj on April 09, 2012, 04:55:08 PM
So, I've been looking through the FR on how to get rid of cat heating and secondary air logic.

It seems that SLS is only activated if b_kh=1 or if bit 0 of CWSLS is 1, which means secondary air even when not cat heating. This is set to 0, at least on my RS4.
Now, the german FR document does not seem to detail the BBKHZ function... it is talked about in AK though.

The english Alfa FR has the info.
From looking through it, the cat heating function is _only_ activated, if the PROKON module sets b_katfz to 1.
b_katfz is read from CWKONABG.0 - and this is set to 1 in all files I can see so far.

So I am going to try setting this to 0, since my pre-cats and rear O2's are removed. In fact CWKONABG should just be set to 0, as the only thing it controls is if a cat heater is fitted, cats are fitted or SLS is fitted...
Only have the rear cats - enough to pass the sniffer test at idle (which is how emissions are tested here).

This should also mean that SAI is not activated and LOADS of fuel is not dumped every cold start bore washing the engine.
Just thought I'd post this up, as searching for CWKONABG yielded no results...


Title: Re: Turning off catalyst heating
Post by: prj on April 10, 2012, 12:35:36 AM
Success, SLS and BBKHZ is never activated anymore :)


Title: Re: Turning off catalyst heating
Post by: marcellus on April 10, 2012, 06:24:43 AM
Whats the difference between what you did and turning off "FKHABMN - threshold terminating factor catalyst heating"? Where did you find CWKONABG?


Title: Re: Turning off catalyst heating
Post by: prj on April 11, 2012, 01:17:08 AM
CWKONABG is in PROKON. Look at Alfa FR.


Title: Re: Turning off catalyst heating
Post by: prometey1982 on October 26, 2021, 04:52:56 AM
Success, SLS and BBKHZ is never activated anymore :)
Thanks prj. I found and disabled it in Volvo BIN.


Title: Re: Turning off catalyst heating
Post by: prj on October 26, 2021, 06:39:12 AM
Post from 2012, I'll leave a word of warning, don't try this on anything newer than ME7, especially not MED17.
On ME7 this is the way to go though.


Title: Re: Turning off catalyst heating
Post by: Tb205gti on December 08, 2021, 08:37:13 AM
Post from 2012, I'll leave a word of warning, don't try this on anything newer than ME7, especially not MED17.
On ME7 this is the way to go though.

Any hints in how to do it on MED17.5?

I have a 1.4 TFSI running really good - but once it goes into "kat heizung" I get "too rich bank2" 35% of the time. I'd like to completely disable the kat heizung on it.

There must be some temperature limiter that I can raise/lower to ensure it never happens?


Title: Re: Turning off catalyst heating
Post by: tom-k on December 13, 2021, 02:53:30 AM
It`s very easly: codeword set to 0


Title: Re: Turning off catalyst heating
Post by: 4ringpieces on April 29, 2022, 11:31:01 AM
Anyone know why not to do this on newer than ME7?

looking set CWKONABG to 0 on a MED9.1


Title: Re: Turning off catalyst heating
Post by: Vollmer on May 06, 2022, 05:14:35 PM
Same question..

Mine is 0.. Starts up cold and idles ~900.
Not sure how I ended up at this conclusion.

01 AWM A4 B5 1.8T