| 摘要 |
<p>To provide an oil degradation determining device for an internal combustion engine, which is able to determine degradation of oil accurately regardless of a driving state of a vehicle. An EFI-ECU 41 estimates an amount of sludge precursor accumulated in an oil pan 4 based on temperature of an engine 1 and an injection quantity. Particularly, the EFI-ECU 41 calculates an amount of fuel injected in a combustion chamber 7 of the engine 1 per certain detection period including detection time, estimates an amount of sludge precursor accumulated in the oil pan 4 based on a calculated value of the accumulation amount of sludge precursor per unit amount of fuel, which is calculated based on current temperature of the engine 1, and a calculated value of the amount of fuel injected in the detection period from previous detection time until current detection time, and judges that engine oil O is degraded when the accumulation amount of the sludge precursor becomes a certain value or above.</p> |
