A petrol vehicle typically uses a spark-ignited internal combustion engine. In a spark-ignited system, the fuel is injected into the combustion chamber and combined with air. The air/fuel mixture is ignited by a spark from the spark plug. Petrol cars are available in either manual and automatic transmission.

Petrol cars are the second most popular new car choice for Irish motorists, with their market share currently at 38% in the new car market, which has been increasing in recent years.

While CO2 emissions from petrol tend to be higher than an equivalent diesel vehicle, they are better from an air quality (NOx) perspective. Fuel costs, due to both higher fuel duties and fuel efficiency, tend to be higher when compared to a diesel equivalent, but servicing costs are lower. The petrol car is perfectly suited to urban driving and commuting journeys. It has lower NOx emissions than diesel cars meaning improved air quality. Petrol cars have lighter engines with quicker responsiveness.