What is the correct sequence of steps in four stroke engine cycle?

The four-stroke engine cycle refers to the sequence of events that occur during one complete cycle of operation in an internal combustion engine. The four strokes or processes involved are:

1. Intake stroke (suction stroke):

- The intake valve opens, and the piston moves down the cylinder, creating a low-pressure area.

- The air-fuel mixture (in gasoline engines) or air (in diesel engines) is drawn into the cylinder from the intake manifold.

2. Compression stroke:

- Both the intake and exhaust valves are closed.

- The piston moves up, compressing the air-fuel mixture, which increases its pressure and temperature.

3. Power stroke (expansion stroke):

- The spark plug (in gasoline engines) ignites the compressed air-fuel mixture, causing a rapid expansion of gases.

- This expansion forces the piston down, generating power.

4. Exhaust stroke:

- The exhaust valve opens, and the piston moves up, pushing the burnt exhaust gases out of the cylinder and into the exhaust manifold.