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.
On Hybrid vehicles the hood will need to be open to perform the procedure.
In some instances the system can change to high pressure mode before the engine speed listed when the PCM detects that the engine load increases above a calibrated threshold. This can sometimes be determined by monitoring the oil pressure reading. Typically pressure will increase in relation to engine speed. When the system changes modes the pressure may spike suddenly up or down depending on which mode is being commanded.
Consult the oil pressure specifications in the table below:
| 2.0L GMET 4 (DOHC ENGINE) 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) |