DSL-202 Chap 16: Functions of High Pressure Fuel Systems

Which diesel fuel injection system is one of the most commonly used today?

• Common rail

• PT pump

• Port helix

• Pressure timed

Increasing fuel atomization injection pressures promotes __________.

• Increased fuel economy

• Lower cylinder pressure

• Lower cylinder heat

• Less air required for combustion

Which engine system is the most expensive to manufacturer?

• Turbo charging

• Fuel system

• Valve train

• Cooling system

Which of the following is NOT a task of the high-pressure injection system?

• Meter the correct quantity of fuel for injection

• Time the injection of fuel

• Atomize the fuel

• Filter the fuel

Calibration coding may be expressed as __________.

• The injector calibration code

• The E-trim

• Injection quantity adjustment (IQA)

• All of these are correct.

A coolant temperature sensor would fall under which category of operation?

• Processor function

• Input data

• Output actuator

• Driver information only

Technician A says high pressurization of fuel is necessary to penetrate the dense combustion chamber air mass. Technician B says that in today's engines, injection pressures range from a low around 2250 pounds per square inch (psi) (155 bar) during idle conditions, to over 18,500 psi (1276 bar) at high speed under full engine loads. Who is correct?

• Technician A

• Technician B

• Both Technician A and Technician B

• Neither Technician A nor Technician B

On mechanical systems injection, timing needs to be set to within __________ degree(s) of the manufacturer's specifications for correct emission control.

• One-quarter

• One-half

• One

• Two

What is the definition of heat haze?

• Shimmer of heat from the cooling system

• Shimmer of heat from the engine exterior

• Shimmer of heat from the exhaust system

• None of these is correct.

Injection timing on older mechanical engines has to be adjusted to within ____degree for lowest emissions.

• 0.5

• 1.0

• 1.5

• 2.0