Depending on the type of engine, piston, turbine, external, rotary, among others there are numerous components to an engine without which the engine will not function. For example a typical piston cylinder engine(from any car) will not work without any of the following components-piston, carburetor/fuel injection, con-rod, crankshaft, inlet/exhaust valves, camshaft, camchain/timing belt.
An engine is a complex device that requires many finely balanced components to work in harmony. But to pick the most important, it would probably be the crankshaft which is present in any type of engine in some shape or form.
the most important part of a cell, as it contains the cell's DNA
what is the most important body part of a jaguar
PEOPLE
your heart and brain but really every part of you body is very important
The largest or most important part of an organ is called the "parenchyma." This term refers to the functional tissue of an organ responsible for its specialized functions.
the steam engine
its the engine
Is the engine the most important part of a moving car? What about the wheels? A person with good nutrition but without exercise is like a car with a good engine but no wheels.
The engine. Once you replace it with a 5.7L you will have a car that is not slower than a bicycle.
the keystone is the most important part of an arched bridge. :]
The most important part of a watch is battery. With out a battery a watch is dead.
The most important part of the heart is all of it. There all equally as important.
It is somewhat subjective what the most important part of a graph is. It is very important that you label each axis.
the important part of a flower is the xylem timelord
engine
You are the most important
the most important part was the defeat of the Spanish armada