2002 impreza wrx 2.0 misfire on cylinder 2 and 3 at first cleared and now 2 and 4 has new plugs and coils 120 compression on all 4 cylinders #2 passes a leak down test. has new fuel filter . customer did timing belt but had misfires before and after doing belt. takes a long drive to set the code even though you can watch it misfire at idle. injectors seem to be functioning i have a tester that test for the pintle dropping

 

Check the timing belt again.
I had similar once.
garage did belt out by 2 teeth.
luckily car drove ok but took another mechanic to sort it.

 

But if it did it before and after the belt swap . . .

 

Could of been out before, stranger things have happened.