Question id 303 - Preflight Preparation - FAA PPL(A) - Private Pilot Airplane

The excessively rich mixture will create higher cylinder head temperatures and may cause detonation
The fuel/air mixture may become excessively lean
There will be more fuel in the cylinders than is needed for normal combustion, and the excess fuel will absorb heat and cool the engine.

Training tests and timed exam simulations FAA PPL(A) - Private Pilot Airplane