System fault diagnosis method, electronic equipment and readable storage medium

The invention provides a system fault diagnosis method, electronic equipment and a readable storage medium, and the fault diagnosis method comprises the steps: firstly obtaining a maximum value and/or a minimum value of an exhaust back pressure measured value corresponding to the current lift of each cylinder; the maximum value and/or the minimum value of the exhaust back pressure expected value corresponding to the target lift of each air cylinder are/is obtained; according to the maximum value of the corresponding exhaust back pressure measured value and the maximum value of the corresponding exhaust back pressure expected value of each air cylinder under the corresponding lift system, and/or according to the minimum value of the corresponding exhaust back pressure measured value and the minimum value of the corresponding exhaust back pressure expected value of each air cylinder under the corresponding lift system, an exhaust back pressure preliminary diagnosis result of each air cylinder is given; and when