Oil Pressure Regulator Valve: Service and Repair
WM 172619 Removing and installing oil pressure control valve (solenoid valve) on 4.8-litre DFI engines
Tools
Technical values
Preliminary work
Information
If vehicles have fault entries relating to oil pressure, oil pump activation, oil pressure monitoring, etc. in the DME control unit (and a warning light comes "on" on the instrument cluster), proceed as follows:
- Check the oil level.
- Delete related faults.
- Do not replace components, such as the oil pump, oil pressure sensor or oil pressure control valve if you suspect that they are faulty.
If the vehicle has not been driven for a long time (months), the control mechanism in the oil pump can become stiff ("stick").
Very short trips and a lot of loading/manoeuvring can cause the oil to become very diluted => Oil pressure very low. For example, 20 cold starts in quick succession can reduce the viscosity of the engine oil by 30%.
- Change the engine oil. Test-drive the vehicle.
- If error messages/warnings are displayed again, proceed in accordance with the instructions under Guided Fault Finding in the PIWIS Tester.
1. Jack up the vehicle at the points provided.
2. Remove engine underbody panelling. -> 108019 Removing and installing engine guard (underbody panelling) on DFI engines - section on "Removing" 108019 Removing and installing engine guard (underbody panelling)
3. Drain engine oil. For details, see -> 170117 Changing engine oil and oil filter on DFI engines Service and Repair
Information
Component overview
Oil guide housing with accessories
Oil pump, M48 (Turbo shown)
Oil pressure control valve and tool
Removing oil pressure control valve (solenoid valve) on 4.8-litre DFI engines
Information
The oil pressure control valve is fitted in the oil guide housing under the generator between the engine carrier -1- and oil filter -2-.
Installation position of oil pressure control valve
1. Carefully grip the cable plug on the oil pressure control valve with a pointed-nose pliers and release it. Pull off cable plug.
2. Expose cable and set it aside. -cable-
Cable in front of oil pressure control valve
3. Remove screws on joint flange. -1-
4. Carefully lever off the joint flange with a screwdriver => Levering off joint flange. Overcome the resistance of the two sealing rings on the oil pressure control valve while doing this.
Levering off joint flange
5. Fit special socket socket-wrench insert 9753 on a ratchet through the opening in the oil guide housing and loosen cap screw on oil pressure control valve. => Using special socket
Using special socket
6. Grip oil pressure control valve with a relay puller 9235 and turn carefully to remove it. => Removing/fitting oil pressure control valve
Removing/fitting oil pressure control valve
Installing oil pressure control valve (solenoid valve) on 4.8-litre DFI engines
Oil pressure control valve and tool
1. Replace two sealing rings on the oil pressure control valve -4-. Replace sealing ring on joint flange -2-.
2. Coat the two sealing rings on the oil pressure control valve lightly with Vaseline or engine oil.
3. Fit the oil pressure control valve as far as it will go into the oil pump => Removing/fitting oil pressure control valve so that the cable plug on the wire harness can be clipped in later without turning it.
Removing/fitting oil pressure control valve
4. Insert cap screw into the special socket socket-wrench insert 9753 and slide it on over the oil pressure control valve. Tighten cap screw hand-tight. When everything is fitted correctly, tighten the cap screw => Using special socket. => Tightening torque: 40 Nm (30 ftlb.)
Using special socket
5. Slide on joint flange with new sealing ring. Screw in and tighten screws -1-. => Tightening torque: 10 Nm (7.5 ftlb.)
Cable in front of oil pressure control valve
6. Route cable, clip it in and connect cable plug.
Subsequent work
1. Fill in engine oil and check oil level. For details, see -> 170117 Changing engine oil and oil filter on DFI engines Service and Repair
2. Fit engine underbody panelling. -> 108019 Removing and installing engine guard (underbody panelling) on DFI engines - section on "Installing" 108019 Removing and installing engine guard (underbody panelling)