Howdy. An interesting diversion on Christmas Eve!

Secondary air injection is a function I haven't looked into before because my engine doesn't have it and I don't recall anyone asking about it before on here.

I agree that the map is for correcting exhaust backpressure depending on the secondary air mass. I didn't see any more maps in the module SLS 88.150 which controls the secondary air system or the overview module AK 1.10.

The secondary air control is coordinated by the catalyst heating sub-function BBKHZ and is switched in so that condition flags B_SLS (secondary air active), B_SLV (secondary air valve) and B_SLP (secondary air pump) are all equal to 1 when the following conditions are met:

- The condition for catalyst heating B_kh = 1
- imlpr is greater than the threshold value IMLSLMN
- Engine start temperature TMST is between TMSSLU and TMSSLO
- Intake air temperature TANS is between TASLU and TASLO.

It looks like if you set VSLS (the speed threshold at which secondary air injection becomes active) to be a large speed and set Bit 1 of CWSLS = 1 (secondary air only after vehicle speed >= threshold) then it should deactivate the function meaning you won't have to fiddle with any other parameters.

TTQS

Hi.

Yes, VSLS is only related to secondary air injection. As for other parameters, all I can really do is direct you to the abbreviations in module SLS 88.150 on pages 1259-1260 of the funktionsrahmen. If you give me a few days, I could translate the module because it looks quite interesting.

TTQS

SLS 88.150 (Secondary Air Control) module attached to post and on the wiki.

TTQS

No problem.

I hope it helps because it was challenging in places.

TTQS