AF Closed Loop Control

[Rufus]

Hi - Planning a swap of an ‘06 MY K20Z1 & W2M5 into my ‘87 CRX Si. I’m considering use of the KTuner End User ‘05-‘06 RSX / Swap System ECU.

Questions about closed loop Target AF control. I see a “base” Target AF mentioned on the “Closed Loop Settings” page which mostly sets conditions for switching between closed & open loop. There are also Lambda target (and limit) values set in tables vs ECT which override the base Closed Loop A/F target. The targets are set separately for low and high loads

How are low and high loads defined? Based on TPS or MAP values, or ranges, or? Does the ECU interpolate between the high & low target AF’s to determine target AF’s vs load? Or maybe there’s more info on AF control I haven’t found … like maybe a target AF map vs rpm & an engine load proxy? What about AF closed loop control under transient conditions? Thanks.

Regards,
Bob

[KTuner]

RPM and MAP generally play a role in load determination. It does not interpolate. Once you engage enrichment those target tables become the AF targets even if you're able to maintain closed loop through other settings.

[Rufus]

Excellent. Thanks, I understand a little better now

So does KTuner allow closed loop fuel control using target AF’s over the entire speed / load operating ranges when ETC is fully warm? (I.e. with no switching between open & closed loop?)

What authority does the End User have with inputs to accomplish this?

Still having trouble understanding how this would be done with so few AF’s as shown in those 2 tables (vs ECT) … especially without interpolation. Are “high load” and “low load” 100% and 0%?

Afraid I’m still not understanding something basic KTuner does …

Regards,
Bob

[Rufus]

“So does KTuner allow closed loop fuel control using target AF’s over the entire speed / load operating ranges when ETC is fully warm? …
…
What authority does the End User have with inputs to accomplish this?”

I should add … while controlling AF to 14.7 @ low load and 12 @ full load, for example.

[Rufus]

“Once you engage enrichment those target tables become the AF targets …”

Where is enrichment engaged? In a fuel (injector pulse width) table?

[KTuner]

WOT enrichment engagement settings are found in the same section. WOT enrichment target tables are in the tables list. We can't coach you on settings to use to achieve what you'd like.

[Rufus]

Thanks

[Rufus]

Does WOT enrichment only apply at 100% load, and then the AF immediately goes to the base target value as load drops: 99% … 98% … etc? Or is there more to it?

Not looking for any suggested values. Just wanna make I understand what the system capabilities are.

Regards,
Bob

[Linszter]

Does WOT enrichment only apply at 100% load, and then the AF immediately goes to the base target value as load drops: 99% … 98% … etc? Or is there more to it?

Not looking for any suggested values. Just wanna make I understand what the system capabilities are.

Regards,
Bob

There are settings for MAP and TPS to determine WOT.

[Rufus]

Hello. Thanks KTuner & Linszter for patiently answering my questions

While ECT is at normal operating temperature …

Can KTuner operate closed loop using inputs from a) wideband O2, b) rpm, and c) engine load to control mixture ratio over the entire rpm and load operating range of the engine? And can mixtures reported by the wideband O2 sensor be closed loop controlled to various mixture target values set by user inputs?

Does the KTuner modified swap ECU support OBDII CAN-Bus (J1979) communication protocol?

Thanks.

Regards,
Bob