Most likely one of two things:
- ignition: misfire should be setting a code or codes. Should feel a miss under load.
- fuel problem: failing fuel pump, clogged filter, blocked lines. Need to put a good gauge on the fuel rail. May just feel like no power.


Since fly-by-wire, it may be a throttle position sensor. Needs instrumentation in any event.


Suspect you may need a new mechanic.