FIELD: manufacture of engines. SUBSTANCE: housing 12 of injector feeding hydrogen to combustion chamber 3 is provided with through axial and side passages 13 and 14. During suction stroke when lean gasoline-air mixture is fed to combustion chamber 3, side passage 14 is closed with cylindrical surface of plunger 15 pressed by spring 16. At the end of compression stroke before spark forming, bore 18 in plunger 15 is matched with passage 14 admitting hydrogen to combustion chamber 3 through passage 20. Under action of pressure increasing in combustion chamber, plunger 15 continues its up stroke separating passages 14 and 20. Nonproductive injection of hydrogen at expansion stroke is excluded due to shift of sealing ring 19 to upper portion of bore 18 under action of its excessive rubbing against housing 12. Spark plug 9 is mounted at a distance equal to one third of its radius relative to axis of combustion chamber 3. EFFECT: enhanced efficiency. 3 dwg
