Technician A says that the nozzles used by DI combustion engines mix air and fuel faster and produce less combustion noise than nozzles used in IDI combustion engines. Technician B says that before the introduction of electronically controlled DI systems, IDI combustion engines produced less noise with fewer emissions and had higher maximum engine rpm than DI combustion engines did. Who is correct?

Question

Quizplus · Accepted Answer

Technician B is correct because IDI (Indirect Injection) engines were known for producing less noise and fewer emissions compared to early DI (Direct Injection) engines before electronic controls improved DI systems. However, DI engines typically have higher efficiency and power output.

Technician a Says That the Nozzles Used by DI Combustion