All engines have "some" blow by. A healthy engine (fuel, spark & blow by all within norms) will boil the gas out of the oil, provided the oil gets & stays up to temp long / often enough.
So three things could potentially be causing this.
One, rings are shot / blow by is excessive. This, I kind of doubt. It makes sense hypothetically, I guess, but I don't really expect it's the issue.
Two, ignition is incomplete. Again - possible, but if you have a decent idle quality & the engine runs down the road & you've done maintenance (you have, haven't you? cap / rotor / wires / plugs?) then it's probably not the problem either.
Three - fuel leaking from injector or FPR. I've replaced more FPRs than injectors.
Put a fuel pressure guage on it, turn the key on. Observe if it holds steady or leaks down a bit.
If you want to get right to it, pull the air cleaner off & have a wiff of the open throttle body. Smell gas? You shouldn't. If you do, pull the FPR & look for wetness. If none, pull injectors next. Connect everything, turn the key on, watch for anything dripping.