Recently my 97 A4 TDI 110 has started to go into limp mode when accelerating over 80mph. There are no problems accelerating uphill etc at lower speeds, just seems to be 5th gear? I have just been checking all the hoses and found that the small diameter tube from the inlet manifold to ECU pressure sensor was full of liquid. Could this affect anything? I have already changed my maf and boost N75.