Hondata

FlashProManager 4.6.5 (26 February 2025)

• Firmware updated to version 277
• [2012-2015 Civic Si] Added boost target and duty
• [FK8/FL5/DE5] Fixed ethanol boost limit

Download here

Please only post in this thread if directly related to the software release.

Although we have waited for a long time, as a small group of non-mainstream vehicle users, we still sincerely hope that the rev limit adjustment and full-throttle shifting function can be restored, and that 4-bar sensor support can be added.

Can we have more details about what was changed with ethanol with FK8s?? Any chance something buggy with this version?

(Got an FK8 acting as if the ethanol multiplier is not active)

I am having a vehicle that had perfect L.trims with FPM 4.6.4 @e62........ updated calibration with FPM 4.6.5 for a few insignificant changes, and it had wild >25% S.Trims & L.Trims, misfire codes, P0171 lean code etc

Reverted and flashed previous calibration with FPM 4.6.4 back to the car and it went back to flat 0% L.trims and minimal 1-3% S.Trims we have had for months.

The change made was for the FL5, and was an unused table index which could get altered inadvertently so was removed.

Send us the datalogs. A zero LTFT looks more like lambda was not working yet.

Update:

The fact reverting from 4.6.5 to 4.6.4 and getting the vehicle to behave again got me into further troubleshooting and thinking somehow the upgrade must have corrupted something in the software.

Upon this, i fully uninstalled 4.6.4, cleaned up of related system folders, rebooted system, reinstalled 4.6.5, rebooted and then proceeded to re-flash.

The vehicle is now responding properly and trims are normal. Whatever it was software wise, not sure root cause.