Possible Duplicate:
Is running the engine for five minutes before driving beneficial for the car?
My wife, her dad, and my dad says so.
They said that before you drive a car, you need to turn on the car for a few minutes, let the engine heat up, then drive.
My dad has a different theory. You don't need to heat up the engine, however, the engine oil is more well distributed when the car is running for a few minutes with no load.
Which one is right?
How it really works anyway?
Is it even true?
