Misfire

What is your question?

I have a random misfire, sometimes it’s p0302 and p0304 and sometimes I get p0302,p0301,p0304 The code doesn’t pop up when driving there’s no lose of power no hard start. All spark plugs have been changed grounds have been checked and cleaned, fuel injector have been checked. It has been running lean but no code for lean will do vacuum leak test today but I don’t know what else to do

What makes this problem better or worse?

Worse at idle

How long has your 2003 Subaru Impreza had this problem?

Since we bought the car