I guess you could try and see if it is an electric or mechanical problem.
Start it from cold and when it becomes warm and cuts out, try unplugging the empa socket from the metering unit. If it then runs ok (for warm idling), you can measure the temp sensor and/or the current at the empa to isolate whether it is a temp sensor or black ecu problem. If unplugging makes no difference it may be worth looking at the mechanical side to see if the injectors are overfuelling, the metering flap and shaft is sticky, or like dojj says, the mechanical injector is permanently energised.

good luck anyway