The repair tester for Common Rail Injector CRI-1000 simulates the outputs of an Engine Control Unit (ECU), by providing fuel injection control signals, of which the parameters may be set by a user, to drive the solenoid of a common rail injector. The CR injector is fed by a high pressure fuel source, which may be a mechanical manual pump or an electrical motor driven pump or a pneumatic driven pressure booster. Such a test device will fulfill the tasks for checking nozzle spray pattern, injector back leakage and solenoid condition.