FAILURE PREVENTION SYSTEM FOR INTERNAL COMBUSTION ENGINE, INTERNAL COMBUSTION ENGINE AND FAILURE PREVENTION METHOD FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a failure prevention system for an internal combustion engine, the internal combustion engine and a failure prevention method for the internal combustion engine that can avoid abnormal combustion in a combustion chamber caused by mixture of lubricating oil with intake air via blow-by gas due to a rapid increase in the amount of the lubricating oil caused by dilution of the lubricating oil as fuel and thus can prevent failure of the engine when the fuel is leaked into a crank chamber due to failure of a fuel injection system, etc.SOLUTION: A failure prevention system 1 for an internal combustion engine including a blow-by gas recirculation passage 20 for recirculating blow-by gas Gb in a crank chamber 10a to an intake passage 12 has hydrocarbon concentration detection means 30 for detecting a concentration D of hydrocarbon included in intake air (A+Gb+Ge) made to flow into the combustion chamber. When the concentration D of hydrocarbon detected by the hydrocarbon concentration detection means 30 reaches a preset determination concentration threshold value D1 or larger, or when an increase rate ΔD of the concentration D of hydrocarbon reaches a preset determination increase rate threshold value ΔD1 or larger, the operation of the internal combustion engine 1 is stopped.SELECTED DRAWING: Figure 1