A high-sensitivity capacitive oil deterioration and level sensor includes a conductive housing member with an inner surface defining a ground electrode and conductive inner member with an outer surface defining a measuring electrode. The housing member is adapted to provide a fluidic connection between an oil container and a gap between the ground electrode and the measuring electrode. The sensor also includes electronics adapted to employ this capacitor geometry to generate signals indicative of a degree of deterioration and a level of the oil within the gap.