Codes p0300-304

Solid cel not blinking.

No other codes.

Car does not lack power, drove fine 3 miles home after getting cel on the highway.

I’ve replaced all spark plugs. One coil. I’ve disconnected the car battery for 10 mins and the codes return.

No oil on driveway to indicate cracked block. No milkshake in oil.

Maybe unrelated, but 4 days before cel came on the center cluster lcd was black(from heat I assume), turning off and on the car made it come back.

Bad gas maybe? Bad fuel pump? Something deeper?

Would buying an obd2 reader with live readings to see misfire count be worthwhile?