Inventors:
Daniel V. Orzel - Westland MI
William E. Boruta - Dearborn MI
Judith M. Curran - Northville MI
Assignee:
Ford Motor Company - Dearborn MI
International Classification:
F02M 5100
Abstract:
An electronic engine control system for use with differing fuel types, such as gasoline, methanol and mixtures of the two, controls engine operating parameters such as the fuel/air ratio and ignition timing in response to fuel-type indications generated by a fuel type sensor positioned on the fuel line. Changes in the fuel type passing the sensor result in variations in the engine control signals which are effective after a variable delay period elapses. The duration of the variable delay period is altered in response to changes in fuel pump voltage and fuel temperature to form a better estimate of the transport delay experienced by the fuel as it passed from the fuel-type sensor to the engine's fuel intake. A microcontroller delays the control signal changes by retrieving a count value from a two-dimensional lookup table indexed by values reflecting pump voltage and fuel temperature. The count value is placed in a countdown timer which is decremented to zero for establishing a subinterval, at the conclusion of which the current fuel type signal is pushed into a FIFO stack as the oldest stored fuel type value is popped from the stack and supplied to the engine controller.