🔍 Key Concepts

• Diesel fuel system operation – what happens inside the system when the fuel supply is interrupted • Injector pumps and injectors – how they move fuel and what they need in order to work properly • Air in closed fuel systems – how it affects pressure, flow, and engine starting/running

💭 Think About

• When a diesel runs out of fuel, what physically enters the fuel lines and pumps in place of liquid fuel? • Which of these problems would most directly prevent the engine from restarting until the system is serviced? • Think about which choice is an immediate and common issue versus something that would develop slowly over time.

✅ Before You Answer

• Identify which option is directly caused by a loss of continuous fuel flow. • Ask: which problem is commonly solved by bleeding or priming the fuel system after running out of fuel? • Eliminate options that would usually result from long-term wear, contamination, or overheating, not just a brief fuel starvation.