Audi Repair: Oil pressure relief valve, pressure relief valve, audi s4

Question
Vehicle: '93 Audi S4 20v turbo 5 cyl. : I suspect a stuck piston or broken/worn spring in the oil pressure relief valvle so I'd like to check/replace it. The oil temperature sender needs to be replaced also. Do you have a technical diagram or a source to locate these (hopefully free)?

Answer
The URS4 has the AAN engine, if you are going to do technical maintenance like this you really have to buy a manual; available from internet shops like amazon and worth their weight in gold...  I am sorry I do not have a manual for this car...  Let me know how you get on,  Jan