Abstract: Electrical circuitry including a single absolute pressure transducer that is arranged to be exposed to substantially atmospheric pressure during a selected associated internal combustion engine operating condition produces an electrical pressure value indicating signal that is stored only when the pressure transducer is exposed to substantially atmospheric pressure. An electronic data processor unit preprogrammed to calculate a selected engine operating parameter value for the associated engine is preprogrammed to periodically effect a predetermined atmospheric pressure correction of the selected engine operating parameter value when the stored electrical pressure value indicating signal differs in a selected sense from a preselected value.

Abstract: A system for increasing the amount of fuel injected into an internal combustion engine in response to an increase in the manifold absolute pressure greater than a predetermined amount and greater than a predetermined rate. The amount of enrichment is equal to a first value determined by the engine coolant temperature increased by a factor that has an initial value determined by the rate of increase in the manifold absolute pressure and that is varied toward unity at a rate determined by engine temperature. The duration of acceleration enrichment is determined by the amount of change in the manifold absolute pressure and the engine coolant temperature.