Query on diesel engine

[dr. d]

Recently I heard a Toyota staff said that diesel engine should be turned on and let it run for 30 minutes before the first driving every day.

Is this correct?

perhaps the statement was in response to, "how do you adjust the engine?"
some engines indicate adjustments be done when the engine is already hot. i have seen stickers pasted in the engine bay or under the engine hood indicating it.
some engines indicate adjustment be done while the engine is still cold.

or maybe, he was trying to sell you the gas model.
heh heh.