I seem to be missing something.... Return hoses are leaking at all ends, have replaced the hoses, copper washers and one way pressure valve! only leaking on left bank, right bank is fine? Are the hoses supposed to be clamped on with mini jubilee clamps at all? Thanks also... looking to do the cambelt etc as my thermostat is duff. Is it really necessary to loosen the camshaft sprockets when fitting a new belt as per the audi service manuals? I have done 1.8t and 2.5 v6 (vaux) belts before but never had to loosen the spockets off and then tension the belt.? Thanks in advance!