While examining a used fuel injection nozzle(s), one finds worn and enlarged orifices. What does this indicate about that cylinder's performance prior to nozzle replacement(s)?

Correct Answer: Option C — Reduced combustion efficiency, increased ignition delay, reduced atomization, prolonged penetration.

Worn and enlarged nozzle orifices cause poor atomization, larger droplets, prolonged penetration, and reduced combustion efficiency. The larger fuel stream increases ignition delay as time is required to heat and vaporize the coarser droplets.