Abstract: Control method and apparatus for multi-fuel, compression ignition engines. In accordance with the method, a target fuel whose engine operating characteristics are to be duplicated when using fuels other than the target fuel in the engine is selected, and the engine operating characteristics including engine torque versus throttle setting and engine RPM when operating using the target fuel are determined and stored as a desired indicated torque versus throttle setting and engine RPM. Then, when the engine is operating on a fuel, a fuel control input and engine RPM are sensed, the desired indicated torque for that fuel control input and engine RPM is determined, a measured indicated torque for the engine is determined, and a fuel quantity command is adjusted to cause the measured indicated torque to equal the desired indicated torque.