Hyundai: Engine D4FA. Manual - part 81
DIESEL CONTROL SYSTEM
FLA -195
4.
Monitor "FUEL PRESSURE MEASURED", "RAIL PRESS. REGULATOR1", "INJ. PUMP REGULATOR" parameter
on the Scantool.
SPECIFICATION :
Idle(without load)
Accelerating(stall test)
Diagnosis
INJ. PUMP REGULATOR
38 ± 5%
32 ± 5%
duty decreases
FUEL PRESSURE
MEASURED
28.5 ± 5 Mpa
145 ± 10 Mpa
press. increases
RAIL PRESS.
REGULATOR1
19 ± 5%
48 ± 5%
duty increases
Fig.1
Fig.2
Fig.1) The position of curser on the graph represents idle data.
Fig.2) Data during acceleration(stall test).
EGNG013U
NOTE
The waveform of fuel pressure regulator valve installed at high pressure pump(fuel detecting MPROP) shows 38%
duty at idle, duty drops to approx. 32% at acceleration to raise rail pressure. Duty drop means the decrease of
current.
→ Fuel delivered to common rail increases as current drops.
The waveform of rail pressure regulator valve installed at common rail shows 19% duty at idle, duty rises to approx.
48% at acceleration to raise rail pressure. Duty rise means the increase of current.
→ If current rises, the returning quantity of fuel deliverd to common rail decreases and common rail pressure rises.
TERMINAL AND CONNECTOR INSPECTION
E6661C32
1.
Electrical systems consist of a lot of harness and connectors, poor connection of terminals can cause various prob-
lems and damge of component.
2.
Perform checking procedure as follows.
1)
Check damage of harness and terminals : Check terminals for contact resistance, corrosion and deformation.
2)
Check connecting condition of ECM and component connector : Check terminal seperation, damage of locking
device and connecting condition between terminal and wiring.