NefMoto

Following on from this thread:

http://nefariousmotorsports.com/forum/index.php?topic=4674.0title=

With a slightly more useful topic title.

I'm slowly getting to grips with things, but i'm trying to get my head round the EGT Model changes for the rear O2 delete, detailed here:

http://s4wiki.com/wiki/Tuning#Rear_O2_Sensors

I've gone thru this and everything makes sense, right up to the "fix up EGT model".

My car still has the factory cat fitted, but it has no rear o2 sensor, hence the delete.  I think these fixes to the EGT model only apply to cars with an actual decat, to disable the ECU calculating modelled EGT's for the cat?

Since my cat is still there would i be right in thinking i should leave these sections alone? Does the EGT model in any way rely on the rear O2 such that it doesnt work properly with it deleted?

I also noted that the top section tells you to set CLRSKA.0 to 0, but reading the EGT section it seems this if for cat cleaning, and so should probably be left on seen as the cat is still there?

Cheers
Kev

Anyone care to comment?

Cheers
Kev

I have not touched the EGT model... but I am running rear O2 sensors.

I would really like to see more discussion on this topic, since the EGT model section in the S4wiki is severely lacking...

Unplug the rear sensor on a 018CH, and your egt's will read massively high.

So your saying the ECU is using the rear o2 to calculate EGT's of the cat?

When you say unplug, do you mean properly code out and remove, or just yanking the lead?

What happens on ECU's without rear O2's? Do they not calculate cat temperature, or use some other method to calculate it?

Yep, in my car they easily reach 900C with 0.5bar boost

Can you elaborate on this?

Do you have the rear O2 removed?

Have you performed the modifications to the EGT model as suggested by the Wiki?

I have suggested these modifications to EGT model. Currently no mods to ATM. Can not get z_lsv = 1 in precat sensor after removing postcat, see: http://nefariousmotorsports.com/forum/index.php?topic=615.msg58519#msg58519

Theres a lot of info to parse in that thread. It also seems like many folk have got it working, but you've had some specific issues that no-one else has?

So far i've got this:

   CDKAT =0
   CWDLSAHK  =0
   CDHSH =0
   CDHSHE =0
   CDLATV=0
   CDLASH=0
   CDLSH =0
   CWKONLS=1
   CLRSHK = 17
   CLRSKA = 0 (this is a guess based on the above and wiki info, do i want to disable cat cleaning?)
   ESKONF Byte 3 changed from 30 to F0

I'm unsure about CLRSKA being 0, because i still have cat, shouldnt i be leaving cat cleaning enabled?


Readiness isnt a problem for me here in the UK, so long as the fuelling is correct and trims work.

CWKONLS=17 is only applicable for stereo o2 sensors. I updated the wiki for the 4 cylinders.

Have you misread that?

CWKONLS is set to 1

Wiki says: CWKONLS - Vehicles with 4 installed sensors (default value 51 dec), set to 17[44] Vehicles with 2 installed sensors (default value 3), set to 1.

Oh snap, I have badly defined CLRSHK. Just looked in IDA and I was wrong by 1 byte :D IF anyone is using 4B..DC file then CLRSHK is @ 12121

CLRSHK is the codeword to turn off rear O2 corrections right?

So that probably explains your weirdness, you hadnt actually turned it off?

Yes, by the looks of it. I'll recheck all my configuration bytes

I did misread it. My apologies :P

Which file have you modified? 4B...DC maybe? Have you confirmed CLRSKA address via ida?

My file is 8N0906018CB

I havent confirmed the location with IDA, i wouldnt even know where to start. I'm relying on the 018CB definition files which are available on here being accurate.

My modified file is in the "rate my tune" section.

Looks like CLRSHK bit0 did not set z_lsv. Hm... maybe my file is too different from FR that we all have and to set z_lsv I have to do some additional steps...