I?m sorry guys as I know this subject has been beaten to death but I cannot get a definitive answer or results on how to tune closed loop with headers to not only improve commanded vs actual (WB) but more so reduce the amount of random misfires I am seeing. I have read multiple threads and commented on a few but would love to get more opinions or options to try out. I have really only found one thread mentioning random misfires due to headers.
The things I?m seeing are quite a few random misfires and also my wideband does not agree with my narrow bands and I?m trying to close the gap. When I go into open loop my wideband reads about .95 lambda when commanding stoich so I know I need to adjust my MAF table but when I do the CL corrections will just adjust back to what my O2s think are stoich anyways...right? and in CL my LTFTs are always within + or - 2% other then idle its about +5% (well except after I get gas LOL).
When im in open loop I may get 2 random misfires every 5 minutes or so but in closed loop i see from 2-34 on a regular basis. About every 30 seconds to a minute it registers misfires. I am not logging individual cylinders just total misfires seeing as how it only happens in CL. Actually the least amount of random misfires I see while in closed loop are when all setting are factory. also I was holding the gear and throttle (2nd at around 4500 rpm in CL...NO PE) the other day trying to log my switching speeds at higher RPM's and got a P0300 cell pop up and service stabilitrac and 146 misfires...I can only figure it was because of my o2's.
Following other threads these are the changes I have made:
1st attempt:
Closed Loop Proportional Base vs. Airflow Mode (multiply x .95)
Closed Loop Integrator Delay vs. Airflow Mode (multiply x 1.1)
2nd attempt:
Closed Loop Proportional Base vs. Airflow Mode (back to factory settings)
Closed Loop Proportional Gain vs. O2 Error (multiply x 1.1)
Closed Loop Integrator Delay vs. Airflow Mode (back to factory settings)
3rd attempt:
Closed Loop Proportional Base vs. Airflow Mode (multiply x .9)
Closed Loop Proportional Gain vs. O2 Error (multiply x 1.1)
Closed Loop Integrator Delay vs. Airflow Mode (multiply x 1.1)
4th attempt:
Closed Loop Proportional Base vs. Airflow Mode (multiply x 1.1)
Closed Loop Proportional Gain vs. O2 Error (back to factory settings)
Closed Loop Integrator Delay vs. Airflow Mode (multiply x .9)
5th attempt:
Closed Loop Proportional Base vs. Airflow Mode (multiply x .8)
Closed Loop Mode vs. Airflow (decreased to DOD settings for lack of better option or knowledge)
Closed Loop Integrator Delay vs. Airflow Mode (multiply x 1.4)
6th attempt: (current)
Closed Loop Proportional Base vs. Airflow Mode (multiply x .8)
Closed Loop Integrator Delay vs. Airflow Mode (multiply x 1.42)
I have also done a crank relearn for the random misfires
I absolutely understand what Proportional and integral controllers and settings are and maybe im chasing a ghost here but really don?t understand in this application how to adjust for the extended time it takes for the O2?s to respond to errors.
I have not messed with Closed Loop Mode vs. Airflow but have read that this could affect the gains.
the biggest thing I cannot seem to figure out is what settings are the actual transport delay settings ?or am I missing those settings in my tune. I really want to understand what are the actual tables that the PCM use for o2 sensor delay??? I just assumed it was the O2 Proportional Gain vs. O2 Error, but am not exactly positive.
I have seen others say they can narrow in their commanded vs actual while in CL by making the O2 changes and/or changing the switch voltages (which I have not tried yet) but then I have also read (and commented) on threads about switch points not changing actual switching in the E38 or 67?s.
Im kind of at a loss here and any help would be greatly appreciated. Thanks guys. log attached is at current settings.