The engine must be removed with it's alternater, flywheel, radiator, water pump, oil pan, starter, battery, carburetor (if not fuel injected), airbox, fuel pump and fuel line with a fuel source. In order to run safely, it must be mounted to a solid base with at least three seating points.
If it is a newer car, it might also need to be attached to a computer in order to feed the engine signals.
Wet where? On the outside? Or are you pulling the plugs out for examination when the car won't start? If they're wet on the outside, is the liquid on them fuel?
A car engine is a heat engine, but there are various types of heat engines outside the realm of car and truck engines.
You start the engine in neutral.
you engine
??? Huh?
Sure, connect it to the car with jumper cables.
Sometimes when a car over heats and it is really warm outside your car will not start due to " vapor lock "
If the oil is low in your car, it can eventually cause your car to stall and not start. It can also kill your engine.
exhaust sytem making contact with underside or engine mount damaged/worn, the sound will resonate inside the car but not outside.
Not unless it is a carburated engine.
engine
a bad engine