Volvo dash codes ISX engine

[Chamberpains]

They are both fuel pressure codes. Yes it can take a little while for air bubbles to pass through when changing filters or when the fuel system and gets a lot of air in it.

When you turn your key on without starting the engine do you hear your lift pump buzzing nice and loud or Does it sound really choppy? If its really choppy it could be a faulty lift pump or it's sucking air.