Diesel Electronic Injection Systems

Cummins calls their electronic engine control system:

DDEC

CELECT

PEEC

V-MACK

Correct! Wrong!

Detroit Diesel calls their electronic engine controls:

DDEC

CELECT

PEEC

V-MACK

Correct! Wrong!

Technician A says that HEUI (hydraulic electronic unit injector) does NOT require adjustment. Technician B says that an EUI (electronic unit injector) does NOT require adjustment. What is correct?

Technician A

Technician B

Neither A nor B

Both A and B

Correct! Wrong!

With electronically controlled engines it is possible to program _________________.

horsepower

governor type

max road speed

all of the above

Correct! Wrong!

The throttle position sensor assembly on most electronically controlled engines contains:

potentiometer

cruise control controller switch

accellerometer

vehicle speed limiting

Correct! Wrong!

Electronic diesel engines are all programmed to shut down immediately in the event of low oil pressure or high coolant temperature levels.

true

false

Correct! Wrong!

Modern ECM''s electronic circuitry tend to operate at temperatures that would cause them to over-heat if not adequately maintained at a safe temperature. Manufacturers use _________________ to help cool them.

fuel flowing through a cooling plate mounted to the ECM

cooling fins and high air flow

are adapted to the air conditioning system, and uses refrigerant

both A and B

Correct! Wrong!

Active faults, refer to faults or conditions that have previously happened.

true

false

Correct! Wrong!

Inactive faults are faults in memory and are not currently happening.

true

false

Correct! Wrong!

How do the electronic unit injector (UEI) control fuel timing.

by varying plunger stroke

by controlling the EUI solenoid

by altering the fuel rail pressure

by opening the throttle shaft

Correct! Wrong!

Electronic diesel engine fault codes may indicate:

engine overheat

low differential oil

turbo overspeed

all of the above

Correct! Wrong!

Technician A says that to check some injection systems, you can hold down each injector plunger to find the miss or weak firing injector. Technician B says to isolate a faulty electronic unit injector, perform a cylinder balance test, then switch injector positions and retest, to confirm a faulty injector. Who is correct?

Technician A

Technician B

Neither A or B

Both A and B

Correct! Wrong!

In order to read or calibrate an electronic diesel engine using a laptop computer, requires the use of a specific engine adapter or translator and a version of the engine manufacturers software.

true

false

Correct! Wrong!

Technician A says that it is sometimes acceptable to repair electronic engine wiring with solder and shrink tube connections. Technician B says that using a digital volt meter will cause damage to the ECM.

Technician A

Technician B

Neither A nor B

Both A and B

Correct! Wrong!

When voltage tests are made on electronic circuit components, the circuit should be:

open

shorted

energized

grounded

Correct! Wrong!

Which of the following are inserted into ECM and the wiring terminal sockets to enable testing by digital multi-meter probes and minimize potential damage?

cycling breakers

non-cycling breakers

dummy terminals

diagnostic forks

Correct! Wrong!

Which of the following statements is the most correct?

Before disconnecting any electronic connectors, the ignition should be turned on.

Wiggling the wiring and connectors may cause an active fault to become inactive.

It is safe to disconnect individual sensors one at a time while the engine is running.

A powered test light is an important tool for diagnostic procedures.

Correct! Wrong!

Electronic controlled diesel engine ECM operates on a reference voltage of 12 volts, plus or minus 5 volts.

true

false

Correct! Wrong!

A computer system monitors battery charge voltages at all times to ensure:

that the alternator develops the correct amperage output.

the sensors are operating and sending signals with a known voltage input.

to enable the check engine light if a fault is found.

that voltages do not spike and harm light circuits.

Correct! Wrong!

A HEUI fuel injection system involves an engine oil hydraulic system and a diesel fuel hydraulic system.

true

false

Correct! Wrong!

Mechanically actuated injection systems cannot be controlled electronically.

true

false

Correct! Wrong!

A HEUI fuel injection system uses three different hydraulic actuation pressures within its system.

true

false

Correct! Wrong!

The injection actuation pressure control valve, also called the rail pressure control valve, alter the hydraulic pressure in a HEUI system by varying the opening of a drain port.

true

false

Correct! Wrong!

Certain instructions programmed into a PROM, establishing certain minimum and maximum parameters of a fuel injection system, cannot be changed beyond design parameters or possible engine damage and warranty disqualification will result.

true

false

Correct! Wrong!

Customer programmable parameters are those that can be changed at a dealership in order to customize features the ECM can control, as a convenience for the customer.

true

false

Correct! Wrong!

HEUI fuel injector operation involves distinct injection stages. They are:

pre-injection stage

injection stage, which includes pilot, delay and main fuel injection

end of injection stage

all of the above

Correct! Wrong!

If 1000 lbs. of actuation oil pressure was applied to a HEUI injector, what would be the potential injection pressure?

2000 lbs.

3000 lbs.

6000 lbs.

8000 lbs.

Correct! Wrong!

In a HPCR fuel system, fuel delivery pressure to the injectors is controlled by:

the pressure limiting valve

common rail and injector line volume

pump speed and flow

the rail pressure control valve

Correct! Wrong!

In the HPCR fuel injection system, the injector needle valve is opened when:

the solenoid is energized, which increases pressure on the needle valve

the solenoid is de-energized, which increases pressure on the needle valve

the solenoid valve is energized, which decreases pressure on the intermediate valve

the solenoid is de-energized, which increases pressure on the intermediate valve

Correct! Wrong!

Technician A says that the PCM and the electronic unit injector controls the metering of fuel into the cylinder. Technician B says that the PCM and the electronics unit injector controls the timing of the fuel injected into the cylinder. Who is correct?

Technician A

Technician B

Both A and B

Neither A nor B

Correct! Wrong!

With an electronically controlled engine there are usually three wiring harnesses connected to the ECM. These harnesses are 1/ the OEM (original equipment manufacturers) 2/ the actuator harness and 3/ the:

throttle position sensor harness

engine fan control harness

input sensor harness

data link harness

Correct! Wrong!

Engine protection is incorporated into the computerized systems because it can sense:

normal operating speeds

crankshaft or camshaft motion

operator demands

coolant temperature and oil pressure

Correct! Wrong!

Computer controlled injection systems are more accurate than mechanically, hydraulically or pneumatically controlled systems.

true

false

Correct! Wrong!

The hydraulic actuation oil pressure in the HEUI system is controlled by the ECM and the:

fuel pressure sensor

IAP control valve

rail pressure sensor

combination (pairing) of rail and fuel pressure

Correct! Wrong!

The amount of fuel injected by an electronic unit injector is typically expressed as pulse width. Pulse width can be identified with:

degrees of crankshaft rotation

percentage of fuel

time the solenoid is de-energized of energized

all of the above

Correct! Wrong!

Electronic unit injectors are actuated by:

a high pressure fuel pump

a high pressure oil pump

a mechanical injector drive mechanism

an electronic drive mechanism

Correct! Wrong!

An ECM cooling plate is used to:

cool the incoming air for better performance, more dense air

cool the incoming fuel for better performance, less than 150 degrees Fahrenheit

compensate fueling to the engine relative to fuel density

protect electronic units from heat

Correct! Wrong!

In the EUI system, the ECM ____________ to initiate the injection process.

de-energizes the injector solenoid

opens the poppet valve

increases the fuel transfer pressure

energizes the injector solenoid

Correct! Wrong!

The computer controls the fuel injection process by gathering information from the sensors.

true

false

Correct! Wrong!

Which of the following acronyms does not relate to computers and not belong in this list?

ECM

BLT

ECU

PCM

Correct! Wrong!

Input sensors generally monitor engine systems for correct operations. Which is not?

rate of injection

manifold temperatures

air box or plenum pressures

crankshaft speeds

Correct! Wrong!

The modern ECM and its memory systems can store all kinds of information except:

total engine hours

total oil consumption

total idle time

total of starts

Correct! Wrong!

On an electronic engine, which sensor notifies the ECM when a cylinder is in the firing location?

throttle position sensor

throttle validation switch

timing reference sensor

electronic distribution unit

Correct! Wrong!

When trouble shooting new electronic systems with their individual diagnostic trouble codes and related information with your generic scanner or laptop, changes to settings cannot be performed without the:

fault codes numbers

access codes

flash codes

sequence of flashing lights

Correct! Wrong!

In most computerized fuel systems, what is the voltage in the sensing circuits?

2 volts

5 volts

12 volts

24 volts

Correct! Wrong!

If the wire attached to the engine crank or cam position sensor or sensors were to come off, the engine would:

set a code, light SEL, de-rate to a lesser horsepower

set a code, light SEL, continue to operate

would die, or fail to restart after shutdown

depending on the system, all of the above

Correct! Wrong!

Which type of sensor would be a potentiometer?

throttle position sensor

oil temperature sensor

speed sensor

O2 sensor

Correct! Wrong!

At any one particular speed, the output signal of a Hall Effect sensor that would be received by an ECM would be read as a _________________ signal.

AC voltage

DC voltage

digital on/off

analog variable

Correct! Wrong!

Computer memory is considered to be volatile or non-volatile memory. Which of the following would be considered volatile?

EEPROM

RAM

ROM

FEPROM

Correct! Wrong!

Thermistors, pulse generators and potentiometers are all different types of:

actuators

analog to digital convertors

input sensors

output sensors

Correct! Wrong!

Cummins calls their electronic engine control system:

Detroit Diesel calls their electronic engine controls:

Technician A says that HEUI (hydraulic electronic unit injector) does NOT require adjustment. Technician B says that an EUI (electronic unit injector) does NOT require adjustment. What is correct?

With electronically controlled engines it is possible to program _________________.

The throttle position sensor assembly on most electronically controlled engines contains:

Electronic diesel engines are all programmed to shut down immediately in the event of low oil pressure or high coolant temperature levels.

Modern ECM''s electronic circuitry tend to operate at temperatures that would cause them to over-heat if not adequately maintained at a safe temperature. Manufacturers use _________________ to help cool them.

Active faults, refer to faults or conditions that have previously happened.

Inactive faults are faults in memory and are not currently happening.

How do the electronic unit injector (UEI) control fuel timing.

Electronic diesel engine fault codes may indicate:

In order to read or calibrate an electronic diesel engine using a laptop computer, requires the use of a specific engine adapter or translator and a version of the engine manufacturers software.

Technician A says that it is sometimes acceptable to repair electronic engine wiring with solder and shrink tube connections. Technician B says that using a digital volt meter will cause damage to the ECM.

When voltage tests are made on electronic circuit components, the circuit should be:

Which of the following are inserted into ECM and the wiring terminal sockets to enable testing by digital multi-meter probes and minimize potential damage?

Which of the following statements is the most correct?

Electronic controlled diesel engine ECM operates on a reference voltage of 12 volts, plus or minus 5 volts.

A computer system monitors battery charge voltages at all times to ensure:

A HEUI fuel injection system involves an engine oil hydraulic system and a diesel fuel hydraulic system.

Mechanically actuated injection systems cannot be controlled electronically.

A HEUI fuel injection system uses three different hydraulic actuation pressures within its system.

The injection actuation pressure control valve, also called the rail pressure control valve, alter the hydraulic pressure in a HEUI system by varying the opening of a drain port.

Certain instructions programmed into a PROM, establishing certain minimum and maximum parameters of a fuel injection system, cannot be changed beyond design parameters or possible engine damage and warranty disqualification will result.

Customer programmable parameters are those that can be changed at a dealership in order to customize features the ECM can control, as a convenience for the customer.

HEUI fuel injector operation involves distinct injection stages. They are:

If 1000 lbs. of actuation oil pressure was applied to a HEUI injector, what would be the potential injection pressure?

In a HPCR fuel system, fuel delivery pressure to the injectors is controlled by:

In the HPCR fuel injection system, the injector needle valve is opened when:

Technician A says that the PCM and the electronic unit injector controls the metering of fuel into the cylinder. Technician B says that the PCM and the electronics unit injector controls the timing of the fuel injected into the cylinder. Who is correct?

With an electronically controlled engine there are usually three wiring harnesses connected to the ECM. These harnesses are 1/ the OEM (original equipment manufacturers) 2/ the actuator harness and 3/ the:

Engine protection is incorporated into the computerized systems because it can sense:

Computer controlled injection systems are more accurate than mechanically, hydraulically or pneumatically controlled systems.

The hydraulic actuation oil pressure in the HEUI system is controlled by the ECM and the:

The amount of fuel injected by an electronic unit injector is typically expressed as pulse width. Pulse width can be identified with:

Electronic unit injectors are actuated by:

An ECM cooling plate is used to:

In the EUI system, the ECM ____________ to initiate the injection process.

The computer controls the fuel injection process by gathering information from the sensors.

Which of the following acronyms does not relate to computers and not belong in this list?

Input sensors generally monitor engine systems for correct operations. Which is not?

The modern ECM and its memory systems can store all kinds of information except:

On an electronic engine, which sensor notifies the ECM when a cylinder is in the firing location?

When trouble shooting new electronic systems with their individual diagnostic trouble codes and related information with your generic scanner or laptop, changes to settings cannot be performed without the:

In most computerized fuel systems, what is the voltage in the sensing circuits?

If the wire attached to the engine crank or cam position sensor or sensors were to come off, the engine would:

Which type of sensor would be a potentiometer?

At any one particular speed, the output signal of a Hall Effect sensor that would be received by an ECM would be read as a _________________ signal.

Computer memory is considered to be volatile or non-volatile memory. Which of the following would be considered volatile?

Thermistors, pulse generators and potentiometers are all different types of:

Success!

Heavy-Duty Mechanic - Trucks & Equipment