Hoping someone knows what is causing this issue
2014 Forester 2.5i CVT
91 octane gasoline, Southwest US, usually hot
K&N drop-in filter is the only performance mod other than the tune
Logging with OBD CAN bus, so I'm limited on loggable items
It's just an NA Forester, but I'm enjoying tuning it and may eventually boost it after learning more. The current tune is a big improvement over stock. It has cut over 1.5 seconds off the 0-60 time and fixed the flat spots.
The main issue I'm having is with fuel. I keep leaning out my Fuel map, but under WOT it always logs 13.197 Fuel/Air Commanded (AFR Gas).
- I bought a Wideband O2 to check what the AFR actually is. But found that it closely matches the Commanded AFR.
- Leaning out the Fuel map seem to change the WOT Commanded AFR or WB O2 readings at all.
- WOT is typically in 1.4x load range, when it hits 1.5x range I'm seeing 12.7 AFR and still Commanding 13.197
- I am missing something and not sure what. Any ideas what to check/try?
- Why is it always commanding 13.197 AFR at WOT regardless of what is on the Fuel Map?
The attached .zip file has the full log, ROM .bin, ECU Flash .xml definition, and screen captures
Here is an example of the Commanded AFR and you can see the WB O2 log delay here. Load goes up to 1.55 and the Actual AFR drops to 12.7:
Attachment:
romraiderlog_20251111_063702-WOT-Pull.png [ 106.09 KiB | Viewed 81 times ]
This is the Fuel Map that goes with this log:
Attachment:
EA1M500B_NA_Tune_4.1-OpenLoopFuelingB.png [ 17.94 KiB | Viewed 81 times ]
For comparison, here is a similar, older log and ROM/Fuel Map:
Attachment:
romraiderlog_20251109_130924-WOT-Pull.png [ 61.36 KiB | Viewed 81 times ]
Attachment:
EA1M500B_NA_Tune_3.8-OpenLoopFuelingB.png [ 20.82 KiB | Viewed 81 times ]
