coolant temp corrections vs o2 control

[Andrew38]

hi. have a problem.
winter is coming, so I trying to make cold start perfect.

the problem is that o2 control trying to compensate coolant temp correction to target afr table values. so I have -20-30% short trim swinging up an down - engine don't like that and trying to stall.
when I raise up o2 control operating temperature - that fixed it, but I want fully working o2 control system.

I'm using latest NSP and can wideband.

thanks in advance.

[JimKden]

I had a problem with O2 correction swinging wildly after a firmware upgrade recently. Haltech advised to zero out the Differential table in the O2 setup. All ok now.
But for cold compensation, see the Haltech Youtube video on cold start settings. Matt suggests the only compensation needed is to setup the Post Start table, no Coolant compensation needed.

[Andrew38]

Haltech advised to zero out the Differential table in the O2 setup.

can't find that table. maybe some mistake and it's not "differential"?
coolant temp correction - it's needed when car is not fully warm up (under 70*C) and gets some lean afr spots.

[JimKden]

Sorry wrong term, my bad memory. It's Derivative Gain Fuel Tuning >O2 Control.

At 70C coolant temperature, my Post Start ends at 3 seconds run time (at 40C it ends at 40 sec, no coolant correction).

I do not allow Long term trim below 75C coolant temperature. The short term correction maintains correct AFR to the target after the Post Start enrichment ends. After 75C there is no temperature related correction needed on my car.

Watch the Haltech video.

[impelz06]

I watched the video but what is controlling fueling enrich at different map’s? Is it using stft with the overall post start to get by until at operating temp? I’m definitely all for simplicity and that coolant temp table can be very complex to get dialed in so would rather just use the simple fuel vs temp and time but just want to make sure I’m not missing something.

[JimKden]

Yes, stfc handles the temporary fuel correction.