Alcohol fuel cylinder preheating independent control method and system

The invention discloses an alcohol fuel cylinder preheating independent control method and system. The method comprises the steps that when an engine start signal is received, the current environment temperature is obtained; if the current environment temperature is lower than a preset temperature, the current temperature of cooling liquid of the engine is obtained, and the preheating temperature corresponding to the current temperature of the cooling liquid of the engine is obtained from preheating calibration data and is used as a target preheating temperature; the current temperatures of electric heating devices of electric heating oil injector are obtained, the duty ratios of voltage signals output to the electric heating devices are adjusted according to the difference values between the current temperatures of the electric heating devices and the target preheating temperature, and therefore the corresponding temperatures of the electric heating devices are adjusted to be identical with the target preheating temperature. By the adoption of the alcohol fuel cylinder preheating independent control method and system, alcohol fuel injected into all the cylinders of an engine can have high consistency, and therefore a good low-temperature start effect can be achieved.