In Petrol Engine Spark Ignited?

A petrol engine or gasoline engine is an internal combustion engine with spark-ignition, designed to run on petrol and similar volatile fuels. In most petrol engines, the fuel and air are usually pre-mixed before compression.

Why are petrol engines called spark ignition engines?

Technically petrol engines are called as spark ignition engines ( SI ) and diesel engines are called as compression ignition engines (CI ) . ... This proves that in petrol engines the compression alone doesn't makes the fuel to burn. Technically speaking this process is governed by constant volume process or Otto cycle.

How is fuel ignited in the engine?

In a spark ignition engine, the fuel is mixed with air and then inducted into the cylinder during the intake process. After the piston compresses the fuel-air mixture, the spark ignites it, causing combustion. The expansion of the combustion gases pushes the piston during the power stroke.