run a lighter weight oil during the cooler months. i ran 20w50 in the summer and 15w40 in the winter.
if it takes a long time to warm up the car, throw in a higher temp t stat durning the winter as well, but run a lower during the summer.
and the higher idle is based off the o2 sensor, ecu reading of water temps, and few other measurements. basically the ecu is trying to get the motor to op temp quicker.
I know a lot about cars. I can look at a car's headlights and tell you exactly which way it's coming