I bought my 2014 four years ago. Now have 265k and I’m getting some herd knocks on start up occasionally. For first time ever the engine light was on. Codes 0300, 302, 303, 304. All have went away. I’ve read about the dreaded head gasket issues. I don’t appear to have lost any coolant. From from I understand, that’s your first indicator that the head gasket replacement is coming soon right? I am near 100% certain there is no record of this car having its spark plugs replaced- so couldn’t that be the logical first step to try and remedy? I drove 55-60 mph 100 miles each day. Have no issue getting 50+mpg each fill up, runs like a dream otherwise. Love my Prius. iPhone ?
