Technician A says modern common rail (CR) refers to a classification of high-pressure fuel injection systems in which pressurization of fuel is accomplished independently of engine speed. Technician B says fuel injection pressure is matched to optimal values required for the most efficient combustion, lowest emissions, highest power output, and best fuel economy. Who is correct?

Technician A says the basic concept of common rail injection is simple: supply fuel at injection pressure to a fuel nozzle that electrically controls the injection event. Technician B says the common rail system's modular design lends flexibility for adaptation to any new or updated diesel engine design. Who is correct?

What do greater rate-shaping capabilities do?

The name "common rail" may also be called __________.

Beginning of injection occurs when the __________.

Technician A says the difference between the CRS1 and CRS2 injectors is in the nozzle. Technician B says the nozzle valve closing speed is determined by the flow through the inlet orifice. Who is correct?

Which of the following statements about Siemens CR injectors injection is NOT correct?

Fuel drained from the Denso injectors is directed to the __________.

Technician A says piezoceramic actuators are more durable than servo-hydraulic actuators, which have greater wear rates. Technician B says because most heavy-duty engines do not commonly exceed 2500 RPM, the servo-hydraulic actuators are able to respond faster and with an adequate number of injection events. Who is correct?

When discussing common rail fuel systems; Technician A says to minimize parasitic loss, newer high-pressure fuel pumps have inlet metering capabilities . Technician B says the metering capabilities of newer high-pressure fuel pumps will increase engine power output and fuel economy. Who is correct?

When will the flow-limiting valve reset?

Technician A says the CP2 Bosch pump is a three-piston pump used on commercial vehicles. Technician B says the CP3 pump is a third-generation axial piston pump used with second-generation CRS2 injectors. Who is correct?

Parasitic loads of a high-pressure pump can reach lost horse power of __________.

Technician A says the high-pressure pump is driven at engine speed and coupled to the engine through a gear drive mechanism. Technician B says the torque required to turn the high-pressure pump is as little as 6 ft-lb (8.1 Nm). Who is correct?

A fuel mass observer algorithm is compared to a volume of __________ in the exhaust flow.

Fuel quill tubes are located within the __________.

How many fuel return flows can be measured in a modern HPCR-fueled engine?

To detect a leaking common rail injector to fuel return, what must the technician do?

Fuel quill tubes are sealed by __________.