Fuel Pressure Regulator 2
The engine control module (ECM) controls the fuel rail pressure using two pulse width modulated fuel rail pressure regulators. Fuel pressure regulator 2 is located on the end of the fuel rail and meters the amount of fuel being returned to the fuel tank. The ECM varies the pulse width modulated voltage to the fuel pressure regulator 2 to relieve excessive fuel pressure which returns to the fuel tank. When the ignition is OFF, fuel pressure regulator 2 opens to bleed off the pressure in the fuel rail.
The ECM controls fuel pressure in three different operating modes. The ECM commands fuel pressure regulator 2 to control fuel pressure at idle and commands fuel pressure regulator 1 to control fuel pressure when engine speeds are above 1700 RPM. Under certain conditions both regulators are used to control fuel pressure.
| Engine Speed | Low Current Service Limit | High Current Service Limit |
|---|---|---|
| Operating Conditions: Engine at normal operating temperature, stable idle, and fuel temperature greater than 15°C (59°F). | ||
| 640 RPM | 185 mA | 833 mA |
| 800 RPM | 252 mA | 969 mA |