Theory Of Operation

WARNING: This page is about a different car, the 2016 Dodge Journey and 2015 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.

The Dual Stage Engine Oil Pump uses vanes and a moving element that is controlled by an solenoid to produce oil pressure to the engine in two regulated pressure stages (Low/High). In low pressure mode, the oil pressure will increase naturally with engine speed. When switched to high pressure mode the oil pressure is increased and is fairly steady. The Oil Pump Solenoid, mounted on the pump, is used to vary the displacement of the oil pump. The Powertrain Control Module (PCM) controls the solenoid operation. When the solenoid is energized, a bypass oil circuit is opened. This changes the eccentricity of the mechanical pump and lowers the oil pressure. The Engine Oil Pump is operated in low mode during most operating conditions to reduce engine load, increasing the efficiency of the engine. The pump is switched to high mode when engine operating conditions require a higher oil pressure. This is achieved by de-energizing the solenoid.

The minimum engine oil pressure is 80 kPa (11.6 psi) for any operating condition. Anything less than this pressure could result in damage to critical moving parts. The maximum engine oil pressure is limited to 1000 kPa (145 psi) by the pressure relief valve. The oil pressure in the main oil galley of the engine can be checked by monitoring the Engine Oil Pressure (EOP) Sensor on the scan tool or using a mechanical oil pressure gauge.

COMPONENT FUNCTIONAL DESCRIPTION - OIL PUMP SOLENOID

The mechanical Engine Oil Pump operates in two pressure modes described below. The Powertrain Control Module (PCM) switches the pump between modes based on the oil temperature, coolant temperature, and engine operating conditions.

Low Mode: To operate the pump in low mode the PCM commands the High Side Driver (HSD) control on, energizing the Oil Pump Solenoid. The Engine Oil Pump is operated in low mode between idle and approximately 2600 RPM.
High Mode: To operate the pump in high mode the PCM commands the HSD control off, de-energizing the Oil Pump Solenoid. The PCM will typically switch the pump from low to high mode when the engine speed increases over approximately 2650 to 2800 RPM.

See the oil pressure specifications in the table below:

OIL PRESSURE SPECIFICATIONS

ENGINE SPEED	OIL PUMP MODE	OIL PRESSURE SPECIFICATION
Idle (750 RPM)	Low Pressure Mode (Solenoid on)	80-160 kPa (11.6-23.2 psi)
1000 - 2650 rpm	Low Pressure Mode (Solenoid on)	110-200 kPa (16-29 psi)
Above 2800 RPM	High Pressure Mode (Solenoid off)	310-390 kPa (45-56.6 psi)