[nbleak21]

"operating temp" can mean thermostat open, or 02 catalyst temp is hot enough for closed loop, both of which can decrease dramatically in the winter causing the vehicle to go back into open loop, especially those of us running leaner then stoich! (EOC, DFCO, Lean burn, etc)

FMU is an analogy for Fuel Management Unit. I run a VAFC (piggyback microprocessor that wires into the ECU and engine sensors) in my acura to lean the engine out during light load cruising, and to dump a little extra when I get on it to compliment I/H/E. (pic of VAFC attached)

unsure how familiar you are with torque, but you can build custom monitoring pages that really help out with F/E. (screen shot attached)