1 The burning gases can ignite the lean mixture.

2 The engine will not run well a lean mixture and may stumble or stall.

3 A lean mixture combustion system is presented in this paper. And the test effect of fuel injection time, fuel adjustment, miximum load speed and emission characteristics are analysed.

4 In order to cater to the needs of lean mixture combustion, the energy for ignition should be increased and the discharging time should be lengthened.

5 The engine will not run well with a lean mixture and may stumble or stall.

6 On the other hand, the fuel consumption of the quasi-homogenous mixture lean combustion decreased by about 6.5% compared with homogenous lean mixture combustion during all the A/F.

7 The stronger air motions are helpful in organizing mixture strength distribution and then realizing lean mixture combustion in two-valve gasoline engines.

8 The adoption of two-stage injection can achieve a quasi-homogenous mixture and realize the lean mixture combustion in the modified 2-Valve gasoline engine.

9 Compared with stoichiometric mixture operation,[] fuel economy and emissions are remarkably influenced by injection timing when lean mixture is applied.

10 The results show that species dispersion has little influence on the gas temperature and reaction heat for the lean mixture.