An embodiment of the present invention provides for a sensing element comprising a non-conductive housing with three chambers for detecting oil conductivity, additive depletion and oxidation, and water contamination, respectively. Through the monitoring of an array of oil sensors, an early warning of oil degradation due to oxidation is provided. The monitoring system further detects excess soot, water and other contaminants in the oil. The oil sensor array and related monitoring system decrease the likelihood of catastrophic engine failure through the early detection and warning of a decrease in oil quality thereby reducing vehicle owner outlays for servicing and disposal fees while further aiding in the satisfaction of environmental protection regulations.