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Re: Air Charge Limit ignored?
Posted: Tue Apr 29, 2025 9:42 pm
by Caustic Gnostic
Alright, I guess I can scrap it and start again, I mostly was just trying to eliminate the high positive trim around 4V. Honestly it didn't make sense since the AFR would go 11's when the pump hit 100%...
Screenshot 2025-04-29 223413.png
Re: Air Charge Limit ignored?
Posted: Tue Jun 24, 2025 7:19 pm
by ARDlta
Having a similar issue myself, did you find a solution? My FK8 is going into open loop at WOT and the AirC and AFR are fluctuating up and down a lot.
Re: Air Charge Limit ignored?
Posted: Tue Jun 24, 2025 8:43 pm
by Caustic Gnostic
I was able to figure this out by tuning the MAF correctly and also updating the AFR table logic.
For the MAF I was not properly understanding when to raise and lower flow values in the table. If the LTFT + STFT >> -3 you can increase the values around that voltage range. Similarly if LTFT + STFT << -3 then you can lower the g/s values in that voltage range. This assumes that you are aiming for an overall LTFT of -3 (you can update if you are aiming for another value). Once you get LTFT of -3 and STFT of around 0 for all voltages you are done. (Sorry if you already did this because I hadn't done it right)
For the AFR tables the thing that helped me the most was making the values equal for AIRC 170%+. Sometimes I would have AIRC values that would fluctuate between bands like 175% -> 190% -> 187% causing the AFR CMD to wildly fluctuate and max out my pump due to the poor MAF tuning.
Lastly for both the MAF and AFR I smoothed out the tables so there were not large jumps.
Re: Air Charge Limit ignored?
Posted: Wed Jun 25, 2025 4:06 am
by ARDlta
Appreciate the reply! I’ve been scaling the stock maf for awhile but was still running into the issue. Found that the car was going into open loop and reading off of different tables, causing the AirC to increase. I think maxing out the stock sensor was part of it.
The CTR500 maf is going into open loop as well, but much less. I think this is due to scaling more than anything. I’ll check the AFR tables as well.
Thank you!