Abstract: There is provided an injector diagnosis system for a motor vehicle having a plurality of injectors mounted on an engine and a control unit for generating a pulse signal to control the injectors. A sensor detects a current which is supplied to the injectors when the pulse signal is generated. A calculator calculates an injector load current on the basis of the current detected by the sensor. A diagnosis device determines whether the injectors are normal by comparing the injector load current and a reference current. A judging device judges whether a fuel cut condition is satisfied on the basis of signals from various sensors which detect driving states. And an instruction device operates the diagnosis device to stop the determination when the judging device judges that the fuel cut condition is satisfied, whereas the determination is executed when the judging device judges that the fuel cut condition is not satisfied.