Application of Metal Oxide Gas Sensors for the Detection of Fuel Contamination in ICEs Oil

In modern internal combustion engines, oil represents a real component. It carries out the essential tasks: lubrication and heat dissipation. On one hand, it directly influences the vehicle performances and, on the other hand, it is subjected to an unavoidable dirtying and degradation process during operation. For these reasons, it requires a dedicated maintenance program which traditionally consists in a scheduled substitution without the analysis of its actual state. To this purpose, the current work aims to show the potential use of nanostructured metal oxides (MOX) gas sensors to develop a new online, on-board, non-invasive device for the oil monitoring. Indeed, they could analyze the oil vapors from the recirculation pipe directly in the engine head. For this analysis, two traditional engine oils have been considered and used in the same test bench. It is equipped with a small spark ignition engine operated in different conditions and fed in turn with different fuels or blends (gasoline, ethanol, and methanol). Besides, a set of MOX sensors, based on traditional and advanced materials, has been realized with thick film technology. The correlation between the oil sample state and its vapor composition monitored by MOX sensors has been investigated confirming the possibility to realize an online device.