Denso 4D56 Service Manual page 17

Operation Section
1 12
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(1) SCV Opening Small (Duty ON time long - Refer to the "Relationship Between Actuation
Signal and Current" Diagram.)
• When the opening of the SCV is small, the fuel suction area is kept small, which decreases the transferable fuel volume.
(2) SCV Opening Large (Duty ON time short - Refer to the "Relationship Between Actuation
Signal and Current" Diagram.)
• When the opening of the SCV is large, the fuel suction area is kept large, which increases the transferable fuel volume.
Feed Pump
Needle valve Small Opening
Feed Pump
Needle valve Large Opening
Q001114E
Q001115E