Deck 25: Single-Actuator Eui Systems

Question 1

Which was the first computer controlled, truck diesel engine to be manufactured in North America?

A) DDC Series 92 DDEC I
B) DDC Series 50
C) DDC Series 60
D) DDC Series 40

Answer 1

DDC Series 92 DDEC I

Question 2

What engine was the first generation of DDEC electronics (DDEC I) used on?

A) Series 92
B) 60 Series
C) 55 Series
D) 50 Series

Answer 2

Series 92

Question 3

In what MY did single actuator EUIs cease to be used on any North American, Highway certified diesel engine?

A) 1997
B) 2003
C) 2007
D) 2010

Answer 3

2010

Question 4

Which of the following types of throttle position sensors (TPS) would be used on most diesel engines fueled by single actuator EUIs?

A) Potentiometer
B) Variable Capacitance
C) Hall-effect
D) Acoustic

Question 5

Which of the following is NOT true of the signal voltage value returned by a potentiometer type TPS if it is functioning properly?

A) varies proportionally with pedal travel
B) must be less than V-Ref value
C) lowest value is at zero pedal travel
D) digital PWM format

Question 6

How is EUI duty cycle usually displayed on electronic service tools (ESTs)?

A) crank angle degrees
B) pulse width (PW)
C) on-off duration
D) cubic mm of fuel pumped

Question 7

What force is used to convert charging pressures into injection pressures in EUIs?

A) electronic from control cartridge
B) electrical from injector drivers
C) hydraulic from fuel sub-system
D) mechanical from injector cam profile

Question 8

What mechanical feature defines the limits within which EUI fuel pulse width (PW) must take place?

A) injector cam profile
B) camshaft position signal
C) valve cam profiles
D) crankshaft position signal

Question 9

Which of the following terms used by DDC to describe DDEC EUI fueling has the same meaning as split shot injection?

A) pilot injection
B) detonation
C) quiescent combustion
D) maximizing injection pressure

Question 10

When a typical EUI is managing pilot injection, when should the second pulse begin?

A) at 15 degrees ATDC
B) the moment the pilot pulse ignites
C) peak cylinder pressure
D) during afterburn

Question 11

Which of the following is NOT an advantage of pilot injection?

A) reduced engine wear
B) lower cold-start emissions
C) detonation avoidance
D) extended EUI service life

Question 12

What does the injector response time (IRT) allow DDEC electronics to do when managing EUI pulse width?

A) compensate for minor EUI circuit resistances
B) adjust for EUI mechanical wear
C) compensate for a failed EUI control cartridge
D) adjust EUI firing sequence

Question 13

When a single-cylinder cutout test is being performed on a typical EUI-fueled engine with the objective of identifying a dead cylinder, what happens to mean (average) PW when the EUI over the dead cylinder is cut?

A) mean PW increases
B) mean PW does not change
C) mean PW decreases
D) engine rpm drops by approximately 17 %

Question 14

What electronic component houses the electronic distributor unit (EDU) in versions of DDEC fueled engines manufactured before 2007?

A) ECM
B) PCM
C) MCM
D) CPC

Question 15

A Series 60 engine equipped with N2 injectors is being tuned up using the DDC service literature procedure. Technician A says that when the valves at cylinder #4 are at overlap, the EUI height may be set at cylinder #6. Technician B says that in this position, the valves at cylinder #3 may also be set. Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 16

What is the acronym Caterpillar use to describe their EUIs?

A) ADEM
B) ACERT
C) MEUI
D) HEUI

Question 17

Identify the ACERT equipped engine in the list below:

A) C15
B) C-15
C) 3406E
D) C-10

Question 18

What type of transfer pump is used in the fuel sub-system in most EUI-fueled engines?

A) fixed clearance gear pump
B) helical gear pump
C) plunger pump
D) vane type pump

Question 19

Which of the following must happen to enable an EUI to no-fuel, and therefore shutdown, an engine?

A) EUI solenoid not be energized
B) no plunger stroke
C) camshaft does not ramp off IBC
D) camshaft ceases to rotate

Question 20

Which of the following determines the length of a plunger effective stroke in a single actuator EUI?

A) length of plunger downstroke
B) cam lift
C) time EUI control solenoid is energized
D) the duration of the TPS signal

Question 21

Which of the following values is typical of NOP of most 2-terminal EUIs?

A) 3,500 psi
B) 5,000 psi
C) 12,500 psi
D) 25,500 psi

Question 22

When the control cartridge is energized in a typical single actuator EUI, which of the following passages is immediately closed off?

A) cylinder head return gallery
B) EUI pump chamber to nozzle duct
C) nozzle valve pressure chamber
D) EUI control valve spill

Question 23

When Caterpillar single actuator MEUIs are energized by the ECM drivers, voltage peaks at:

A) 5 V-DC
B) 8 V-DC
C) 12 V-DC
D) over 100 V-DC

Question 24

What voltage are DDEC single actuator EUIs switched at?

A) 5 V-DC
B) 12 V-DC
C) 78 V-DC
D) over 100 V-DC

Question 25

What voltage are Cummins CELECT EUIs switched at?

A) 5 V-DC
B) 12 V-DC
C) 78 V-DC
D) 100 V-DC

Question 26

When a four-cylinder cutout test is being performed on an engine, what is the minimum number of cylinders that should be firing during the test cycles if all the EUIs are functioning properly?

A) One cylinder
B) Two cylinders
C) Four cylinders
D) Six cylinders

Question 27

Besides identifying a dead cylinder, what else can a multi-cylinder cutout test identify after performing a cylinder cutout test?

A) emissions analysis
B) cold engine operation
C) unbalanced cylinder fueling
D) all of the above

Question 28

Which of the following tests is executed by electronically cutting out EUIs in a sequence?

A) Cylinder contribution test
B) Engine balance test
C) Injector cutout test
D) All of the above

Question 29

When an engine is key-on and engine-off (KOEO), the EUI solenoids can be heard to rhythmically click in sequence. Which of the following is likely to be true?

A) a state of health (SOH) is being run
B) a failed EUI has been detected
C) system electrical failure
D) connect an EST to troubleshoot

Question 30

Which of the following values represents a typical charging pressure in EUI-fueled engines built before 2007?

A) 30 psi
B) 60 psi
C) 120 psi
D) 5000 psi

Question 31

Where do Caterpillar usually locate a hand priming pump in their EUI-fueled engine?

A) on the secondary filter housing
B) at the fuel tank pick-up tube
C) at the gear pump inlet
D) on the primary filter housing

Question 32

What does the control cartridge mechanically move to manage an effective stroke in a single-actuator EUI?

A) pumping plunger
B) barrel
C) nozzle needle
D) poppet control valve

Question 33

When an EUI control solenoid is energized, which of the following is immediately closed?

A) cylinder head return circuit
B) pump chamber to nozzle duct
C) nozzle needle pressure chamber
D) EUI spill circuit

Question 34

What pressure is used to charge Cummins CELECT Plus injectors?

A) they are under suction
B) 78 psi
C) 150 psi
D) 285 psi

Question 35

Where does return fuel exit a CELECT Plus injector after the injection pulse?

A) metering spill port
B) fuel drain in upper annulus
C) cup
D) inlet in the lower annulus

Question 36

Which of the following describes the role of fuel that enters the timing chamber in a CELECT Plus injector?

A) keeps the metering checkball seated
B) hydraulic link between timing and metering plungers
C) keeps the spill passage sealed
D) loads the nozzle valve closed until the control solenoid is energized

Question 37

Which domestic engine manufacturers of onhighway commercial diesel engines are using single-actuator EUIs after the EPA 2007 model year?

A) DDC only
B) Volvo-Mack only
C) Caterpillar only
D) None

Question 38

Technician A says that failure to reprogram injector calibration codes to the ECM after an EUI change-out result in unbalanced fueling. Technician B says that most OEMs require EUI calibration codes to be reprogrammed each time an injector is changed out. Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 39

If an injector calibration code is inscribed as A, B, or C, what is the likely engine application of the EUI?

A) 1st generation DDEC
B) Late generation DDEC
C) 1st generation Volvo
D) Late generation Caterpillar

Question 40

What what you be looking for when attempting to identify a Caterpillar E-Trim code?

A) single digit alpha
B) two digit numeric
C) four digit alpha
D) four digit numeric

Question 41

What would be the performance consequence of failing to reprogram an EUI calibration code when an injector is changed out?

A) rough engine operation
B) engine runaway
C) lower idle speed
D) higher idle speed

Question 42

Technician A says that to program EUI fuel flow rates to an ECM, some engines require a new engine file to be downloaded from the OEM data huB. echnician B says that failure to reprogram the calibration code on injector change-out is unlikely to cause any harm providing the engine runs smooth at idle after start-up. Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B