Pressure control valve
Recommend retail price $680. (Obviously dealer dependant)
Part # G*8971748720
The rail pressure control valve is in the high pressure oil circuit.
It is an important device which is used to control oil pressure in the HEUI system.
Symptoms if faulty (these occurred to me and replacing the valve fixed all of them MAY 2009)
1/ shuddering or missing like petrol engine
2/ below average horse power and performance
3/ slight rise in fuel consumption
4/ delayed auto change down and laboring in all gears
Generally a good strip and clean of the mechanical parts would suffice but my valve had substantial corrosion which prevented smooth operation.
Speaking to the mechanic who found and cleaned mine said a lot of the problems associated from dirty oil.
Being either from not changing the small oil filter regularly enough this will cause a blocked filter and the bypass valve will open allowing unfiltered oil into the fuel pump side circuit or letting the oil degrade leaving residual deposits of crud.
In my case the previous owner doing too many short trips to get the paper and not getting engine oil to operating temperature to evaporate condensation.
Preventative maintenance would suggest frequent oil and filter changes (including small one), a few extra dollars every 5000klms will save break downs due to bad oil condition.
To replace or disassemble the control valve DIY.
1/ Check if you have a selection of 1 1/8 open spanners or tube socket.(a normal socket wont fit around the flange)
2/ good idea to check if dirt or sand are in the area because you are going to expose the high pressure oil pump to contaminates
3/ good light this fella is in a bad spot
4/ remove passenger front wheel or jack up so it drops away. ( Rh drive vehicle)
5/ remove small rubber skirt to gain access to engine bay from wheel arch
6/ identify valve and disconnect electrical connection it has small clip just for added fun
7/ remove pressed metal nut, sleeve and coil.
8/ using 1 1/8 spanner or tube socket unscrew valve from pump
9/ the valve does come apart by unscrewing the front part where the oil holes are (mine had vice grip marks on it).
10/ inspect condition and clean
11/ carefully reassembly not to over tighten pressed metal nut
Hopefully youve got good results.
Cheers Diemonty
![pressure control valve location.jpg]()
![pressure control valve side view.jpg]()
![pressure control valve pressed nut.jpg]()
see diagram pdf file zipped
![Attached File]()
Pressure control valve.zip 299.73KB
742 downloads
Recommend retail price $680. (Obviously dealer dependant)
Part # G*8971748720
The rail pressure control valve is in the high pressure oil circuit.
It is an important device which is used to control oil pressure in the HEUI system.
Symptoms if faulty (these occurred to me and replacing the valve fixed all of them MAY 2009)
1/ shuddering or missing like petrol engine
2/ below average horse power and performance
3/ slight rise in fuel consumption
4/ delayed auto change down and laboring in all gears
Generally a good strip and clean of the mechanical parts would suffice but my valve had substantial corrosion which prevented smooth operation.
Speaking to the mechanic who found and cleaned mine said a lot of the problems associated from dirty oil.
Being either from not changing the small oil filter regularly enough this will cause a blocked filter and the bypass valve will open allowing unfiltered oil into the fuel pump side circuit or letting the oil degrade leaving residual deposits of crud.
In my case the previous owner doing too many short trips to get the paper and not getting engine oil to operating temperature to evaporate condensation.
Preventative maintenance would suggest frequent oil and filter changes (including small one), a few extra dollars every 5000klms will save break downs due to bad oil condition.
To replace or disassemble the control valve DIY.
1/ Check if you have a selection of 1 1/8 open spanners or tube socket.(a normal socket wont fit around the flange)
2/ good idea to check if dirt or sand are in the area because you are going to expose the high pressure oil pump to contaminates
3/ good light this fella is in a bad spot
4/ remove passenger front wheel or jack up so it drops away. ( Rh drive vehicle)
5/ remove small rubber skirt to gain access to engine bay from wheel arch
6/ identify valve and disconnect electrical connection it has small clip just for added fun
7/ remove pressed metal nut, sleeve and coil.
8/ using 1 1/8 spanner or tube socket unscrew valve from pump
9/ the valve does come apart by unscrewing the front part where the oil holes are (mine had vice grip marks on it).
10/ inspect condition and clean
11/ carefully reassembly not to over tighten pressed metal nut
Hopefully youve got good results.
Cheers Diemonty
see diagram pdf file zipped
Pressure control valve.zip 299.73KB
742 downloads