PURPOSE: To relatively control ignition timing and exhaust gas recirculation (EGR) with simple constitution, by obtaining a flow almost in inverse proportion to exhaust gas pressure with a common pressure control valve, introducing the atmosphere of said flow to a negative pressure timing advance and an EGR valve and adjusting an advance from balance of negative pressure and atmospheric pressure.

CONSTITUTION: At cold time of an engine, the atmosphere from a temperature sensing valve 15 is introduced to an exhaust gas recirculation (EGR) valve 2 and negative pressure chamber 9, and recirculation is blocked, then a choke valve release device 19 is not operated to obtain an overrich mixture. On the other hand, intake negative pressure is introduced to a negative pressure chamber 7 in a negative pressure timing advance 1, while the atmosphere is introduced a slight amount through a throttle 11 and decreased to low negative pressure to slightly retard ignition timing. When the engine is warmed, the temperature sensing valve 15 introduces negative pressure to both close a check valve 17 and open a choke valve 18. Then exhaust gas pressure, applied to a diaphragm 25 in a pressure control valve 12, is changed in accordance with an engine load, to increase negative pressure in the negative pressure chamber 7, in accordance with a rise of the load, to the advance side, if the load is fully increased, a valve seat 27 is closed to start EGR.