| 摘要 |
PROBLEM TO BE SOLVED: To provide an internal combustion engine capable of performing normal perturbation for a long period of time while following a secular change in the fouling condition or the wearing condition of a valve.SOLUTION: In a gas engine 1 for detecting the air-fuel ratio of stoichiometry by oxygen sensors 11, 15 and performing perturbation by a solenoid valve 21, an A/F valve 22 is provided in parallel with the solenoid valve 21, and the gas engine 1 includes a control part 10 for detecting time deviations T1, T2 of the air-fuel ratio changed by the perturbation and opening the A/F valve 22 according to the time deviations T1, T2 to control the perturbation to be performed in an intermediate region 21a of an opening/closing region of the solenoid valve 21. |
