Systems and method for controlling auto-ignition

A system, comprising:

• a first fuel system operable to deliver liquid fuel to a plurality of cylinders in an engine, the first fuel system comprising a first fuel tank, a common fuel rail, and a plurality of fuel injectors, each fuel injector configured to inject liquid fuel to a respective cylinder of the plurality of cylinders;
• a second fuel system operable to deliver gaseous fuel to the plurality of cylinders, the second fuel system comprising a second fuel tank and a plurality of gas admission valves, each gas admission valve configured to supply gaseous fuel to a respective cylinder of the plurality of cylinders;
• and
• a controller configured to, for each cylinder of one or more of the plurality of cylinders:
• initiate compression ignition of the gaseous fuel and intake air by controlling injection of the liquid fuel to the respective cylinder, the gaseous fuel and liquid fuel provided to the respective cylinder at a first substitution ratio;
• in response to a measured parameter associated with auto-ignition of end gases after the ignition resulting from the injection of the liquid fuel to the respective cylinder, retarding an injection timing of the liquid fuel to the respective cylinder;
• and
• in response to the measured parameter associated with auto-ignition still being present after retarding the injection timing, to adjust the first substitution ratio by adjusting at least one of an amount of the gaseous fuel or an amount of the liquid fuel to a second substitution ratio different than the first substitution ratio.