Subaru XT Turbo

Moin moin, am new here and have a few problems with my Subaru XT. I bought the car last week for € 850.00 in Ebay. Inside it is in top condition. Outside I have to weld some places. My problem is: The car was now 8 years deregistered in a garage. At that time the engine was still running. Now it did not start. I then drained the old petrol and blew out the injection nozzles. I also changed the candles and then jumped it. In the stationary gas it runs well, but when I give gas it starts to jerk and has misigned. I guess the gasoline pump or pressure regulator has not survived the long service life. Does anyone have any idea what fuel pump pressure is needed? The pump is sitting in front of the tank. Apparently has the pressure regulator right at the pump outlet. Or does the engine have another regulator? In other talks in this forum is reported by so-called breakpoints in this vehicle. Does anyone know that? Would be nice if someone can help me.