Outline
Changes the fuel pressure applied to the fuel injector according to engine operation conditions to improve engine output and startability.
The PCM determines the fuel pressure value corresponding to the engine operation conditions based on the each input signal, and drives the spill valve control solenoid valve for optimum control of fuel pressure.
Block Diagram

OPERATION
Directly after engine start
During a cold engine start, the fuel pressure is raised to promote fuel atomization.
Basic Control
The PCM determines the target fuel pressure according to charging efficiency and performs feedback control by monitoring the fuel pressure in the fuel delivery pipe using the fuel pressure sensor.
When idling after engine warm up: Approx. 3 MPa {31 kgf/cm2, 435 psi}
After engine warm up, engine speed is 3,000 rpm or more, charging efficiency is 60 % or more: Approx. 15.0 MPa {153 kgf/cm2, 2176 psi}
Fuel Tank
High Pressure Fuel Pump InspectionAir Fuel Ratio (A/F) Sensor Heater Control
Outline
Based on the control of the A/F sensor heater, a stabilized oxygen concentration
is detected even at low exhaust temperatures, and feedback control of fuel injection
even at cold engine start is made possible for improved cold temperature exhaust
emission performance.
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Relay And Fuse Block Removal/Installation
1. Remove the battery tray..
2. Remove the air cleaner case..
3. While pressing the relay and fuse block upper cover tab in the direction of
the arrow (1) shown in the figure, lift up the relay and fuse block upper cover
in the direction of the arrow (2) to detach the relay and fuse block up ...
Throttle Position (TP) Sensor Inspection
Voltage Inspection
CAUTION:
The inspection cannot be performed with this method correctly if there is
a malfunction of the APP sensor or throttle valve actuator. Verify that no DTCs
related to the APP sensor or throttle valve actuator are stored before the inspection.
NOTE:
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