- Spark plugs: Diesel engines do not use spark plugs to ignite the fuel mixture, instead relying on compression to create the heat necessary for ignition.
- Distributor: The distributor is a mechanical device that controls the timing of the spark plugs in a petrol engine. Since diesel engines do not have spark plugs, they do not need a distributor.
- Carburetor: The carburetor is a device that mixes air and fuel together in a petrol engine. Diesel engines do not use a carburetor, instead using a fuel injection system to introduce fuel into the cylinders.
- Throttle body: The throttle body is a valve that controls the amount of air that flows into a petrol engine. Diesel engines do not have a throttle body, instead relying on the fuel injection system to control the amount of fuel that enters the cylinders.
In addition to these major components, there are also a number of smaller parts and components that are found in petrol engines but not in diesel engines. These include things like fuel injectors, fuel filters, and air filters.
