I bought a one-year-old Sportback 2.0L TDI 140 recently, my first Audi. It has now done 17,000kms, but the oil looks really black. The service book indicates that it was serviced at 15,000kms, I suppose with an oil/filter change. This is my first diesel. Should I go ahead and change the oil/filter now for peace of mind, or is this a normal situation. I half suspect that the French garage did not bother to change the oil properly. The next service is at 30,000kms. Does the ECU monitor oil quality? Apparently to go so long between services, oil has to be good for a long time. The car is still under warrenty, so if I have the oil changed by my local garage, would that affect the warrenty? Any good advice will be very much appreciated. Thanks in advance.