🔍 Key Concepts

• Fuel injection timing in diesel and gasoline engines • Effects of pre-ignition / detonation on engine performance • Relationship between combustion timing, power output, and exhaust characteristics

💭 Think About

• Think about what happens if fuel starts burning while the piston is still moving up on the compression stroke instead of near top dead center. • Which option describes a condition that would reduce useful power even though fuel is being burned? • Compare which choices describe a long, incomplete burn versus a sharp, early pressure rise inside the cylinder.

✅ Before You Answer

• Ask yourself which choice matches early combustion pressure pushing against the rising piston. • Eliminate any options that sound like a benefit (something you would actually want in an engine). • Consider which symptom is most directly tied to incorrectly advanced injection timing, rather than general engine problems like poor atomization or dirty injectors.