POWER TRAIN CONTROL APPARATUS AND METHOD FOR A VEHICLE

In a power train control apparatus including an engine, an automatic transmission having a torque converter, and a control unit for controlling the engine and the automatic transmission, the control apparatus is provided with a microcomputer for calculating and estimating values of the input shaft torque and a gear ratio of the automatic transmission. Various characteristics of the engine and the torque converter are obtained in advance by experiments, such as the relationship between an engine torque and an engine speed, and that between a pump capacity coefficient data and a slip ratio of the torque converter. Thereafter, data tables are made by using these characteristics, and control factors required to control the engine and the automatic transmission are made as an equation in relation to the input shaft torque and the gear ratio so as that they can be calculated by the microcomputer.