Fuel Pressure Regulator Control Inspection

WARNING: Fuel line spills and leaks are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete the "Fuel Pressure Release Procedure".

Fuel Pressure Release

Fuel Pressure Gauge Installation:

1. Install the fuel pressure gauge.
2. Measure the fuel pressure under the following conditions.

Fuel Pressure Regulator Control System Specifications:

3. If the fuel pressure is not within the specification, carry out either Inspection 1 or Inspection 2 as required.

Inspection 1
1. Stop the engine.

New Generation Star (NGS) Tester, Connected to DLC-2:

2. Connect the Special Service Tool (SST) New Generation Star (NGS) tester.
3. Start the engine and run it at idle.
4. Turn the Pressure Regulator Control (PRC) solenoid valve from OFF to ON by using the SIMULATION TEST function and check if the fuel pressure changes.
(1) If the pressure changes, check the following.
- PCM terminal voltage
- Engine coolant temperature signal
- Intake air temperature signal
- Closed throttle position signal

(2) If the pressure does not change, do as follows.
I. Stop the engine.
II. Turn the ignition switch to ON.

Pressure Regulator Control Solenoid Location:

III. Turn the PRC solenoid valve from OFF to ON by using the simulation function and check if the operation sound of the valve is heard.
a. If the operation sound is heard, check the following.
- Pressure regulator

b. If the operation sound is not heard, check the following.
- PRC solenoid valve.
- Wiring between PRC solenoid valve and Powertrain Control Module (PCM) terminal 1B

Inspection 2
1. Stop the engine.
2. Connect the Special Service Tool (SST) New Generation Star (NGS) tester.
3. By using the PID DATA MONITOR AND RECORD function, verify that the PRC solenoid valve is OFF.
4. If the PRC solenoid valve is ON, check the following.
- PCM terminal voltage
- Engine coolant temperature signal
- Intake air temperature signal

5. Turn the PRC solenoid valve from OFF to ON by using the SIMULATION TEST function and check if the operation sound of the valve is heard.
(1) If the operation sound is heard, check the following.
- Loose or damaged vacuum hose between the pressure regulator, PRC solenoid valve, and intake manifold.

(2) If the operation sound is not heard, check the following.
- PRC solenoid valve.
- Wiring between PRC solenoid valve and PCM terminal 1B