NOT having any problem, merely curious about something I’ve noticed for years about car engine rpms. Using my current 2014 Camry as an example.
On a cold engine start the rpms are about 2000 then slowly drop to about 1000 while idling as I’m fastening the seatbelt. By the time I drive a few blocks idle rpms at a stop are slightly less than 1000. By the time I drive about a third of a mile idle rpms at a stop are about 750.
Starting the engine once even partially warmed up, say about a mile driving, the idle rpms drop much faster from the 2000 down to a consistent 750.
So why the slow drop to a slightly higher idle rpm on a cold engine versus the rapid drop to a lower idle rpm when the car has been driven only a short distance and not fully warmed up or when fully warmed up?