Abstract: A control system for automatic transmission is provided in a motor vehicle having an internal combustion engine and an automatic transmission associated with the engine. The engine is operable on a fuel which is a mixture of gasoline and alcohol. The control system comprises an alcohol sensor for sensing the alcohol concentration in the fuel; a first device for deriving an engine load parameter which represents the load applied to the engine; a second device for correcting the engine load parameter with reference to the alcohol concentration sensed by the alcohol sensor; and a third device for controlling a line pressure of the transmission in accordance with the corrected engine load parameter.

Abstract: An air/fuel mixture ratio learning control system for an internal combustion engine using a mixed fuel employs a learnt correction coefficient which is used both in a FEEDBACK mode air/fuel ratio control and in an OPEN LOOP mode air/fuel ratio control. The learnt correction coefficient is derived based on a FEEDBACK air/fuel ratio dependent correction coefficient per one of preselected engine driving ranges and per one of preselected concentration ranges of one fuel component contained in the mixed fuel. The learnt correction coefficient is cyclically derived in a preselected stable engine driving condition during the FEEDBACK mode air/fuel ratio control for updating a previously derived and stored one to minimize a deviation of the FEEDBACK correction coefficient from a reference value.