| 摘要 |
The present invention, which pertains to a device for diagnosing an internal combustion engine that is capable of compression release braking, makes it easy to ascertain whether the compression release brake is working. This device for diagnosing an internal combustion engine (10) provided with an exhaust-valve opening/closing mechanism (30) that can open an exhaust valve (19) during a compression stroke is provided with the following: an engine-speed sensor (25); a compression-release-brake control unit (81) that controls the opening and closing performed by the exhaust-valve opening/closing mechanism (30) so as to activate or deactivate the compression release brake and measures the amount of time it takes for the speed detected by the engine-speed sensor (25) to go from a first threshold to a second threshold when the exhaust-valve opening/closing mechanism (30) is controlled so as to activate the compression release brake and the amount of time it takes for the speed detected by the engine-speed sensor (25) to go from the first threshold to the second threshold when the exhaust-valve opening/closing mechanism (30) is controlled so as to deactivate the compression release brake; and an operation determination unit (82) that uses the difference between the two measured times to determine whether or not the compression release brake is working. |
