Automatically detecting number of working cylinders of motor vehicle - repeatedly checking ratio of engine to wheel speed against ignition rate to assumed number of cylinders

摘要

A method of automatically detecting the number of cylinders of a vehicle engine involves measuring the vehicle speed and drive wheel revolution rate nR during a constant speed period and the number E of ignition or injection pulses per unit time for all cylinders. The ratio nM/nR is determined from 2E/(Z.nR), where nM is the engine speed and Z the assumed number of cylinders. This is compared with stored ratios and the process repeated with different values of Z until agreement is reached. USE/ADVANTAGE - Drive slip controllers for automatic engine type encoding for programming according to vehicle type after first journey.