. The methanol–diesel blend method injects methanol and diesel blend fuel which are premixed into cylinder directly through the fuel injector, this way has disadvantage that the mixing proportion of methanol is restricted and need to add additivesto prevent methanol stratification [12]. The fumigation method uses low-pressure methanol injectors introducing methanol into air intake duct, and mixes with air to form carbureted mixture and then enters into cylinders when inlet valve opening, this method has a high MSP that can reach more than 70% [11,13]. Series of studies [8,11,13,14] showed that fumigation method should bepaidmore and more attention because of practical use, convenient installation and high MSP. However, the methanol fumigation mainly use low-pressure methanol injectors which installed intheintake manifold in previous studies, the temperature of intake manifold decreases significantly because of the evaporation of methanol which the latent heat of evaporation is about 4.53 times that of diesel fuel, especially when MSP increases [8