Originally Posted by unclemat
Nothing to do with turbo. Most people put unnecessary strain on the engines and waste fuel by excessive and unnecessary idling. Including people on this forum.
Note, "drive gently" means staying out of boost and within low rpms (< 2.5-3k is my limit for cold engine).
Btw, also people who warm engine by idling and then stomp on it forget that transmission oil and particularly rear diff oil do not get to operating temperature when sitting idle.
After years of logging it is crystal clear that just because you have heat coming out of the vents and the Temp Gauge reads warm.... don't believe your car is ready to romp. You have to have some road time, some miles at speed. The transmission must be warmed up, your differentials, and don't forget the CV joints in your axels.
The car heats up unevenly in other words. From variations inside the engine itself to the driveline there are not only the lubricants to consider but the metals as well.
It works the other way somewhat, too. Once you have pounded on the car and have it heatsoaked you have gone the other direction. Brake systems are another temperature consideration.
Another negative related to excessive idling, it has a tendency to skew your fuel trims. Idle too long and it can affect your full throttle operation. If you're going to sit for a while, turn it off.