Readiness Monitors
2017 BMW 540i xDrive B58 readiness issue:
Bought the car recently and noticed O2 sensor and catalyst monitors were not getting ready. After that, it threw active grille flap codes P059F/P05A0. I used BimmerUtility to code the active grille flaps as not installed, cleared the codes, and now there is no CEL and no current/pending/permanent codes.
Problem is, after about 500+ miles, these monitors still won’t set:
O2 Sensor: Not Ready
Catalyst: Not Ready
Fuel System: Not Ready
Car enters closed loop, coolant gets to about 226°F, charging voltage is about 14V, and fuel trims/lambda look normal. Car feels completely stock.
ISTA shows S0777: engine tuning suspected/detected by automated check, but I don’t know if the car was ever tuned or just flashed/programmed before.
What should I do next? Revert the grille flap coding and drive again, fix the grille flaps, or reflash/program DME back to stock?