In ______ fuel injection, each fuel injector is screwed into the engine head that extends directly into each combustion chamber. This system also uses a high pressure fuel pump with pressure higher than the combustion chamber.

• A. Port
• B. Direct
• C. Sequential
• D. Indirect

Answer: (B)

Direct fuel injection places each injector directly in the combustion chamber by threading into the cylinder head. Because the fuel must be injected into a highly compressed, high-pressure environment, a high-pressure fuel pump is required to force the fuel into the chamber and achieve fine atomization for efficient combustion. This is different from port injection, where fuel is sprayed into the intake ports and operates at lower pressure, or indirect injection, where fuel is injected into a separate pre‑combustion chamber rather than directly into the main chamber. The term sequential refers to injector timing, not placement, so it doesn't describe a system with injectors extending into the combustion chamber.