Prius Prime--Expected Longevity

Probably was not a regular scheduled maintenance item for Honda either. Spark plugs/valve adjustment is just like water pump/timing belt for my other Toyota. They like to tack on additional items.

 

I just bought a 2018 prius Prime. Hopefully if you charge you battery each and evey night you can do most of your driving on electric only. No engine wear in electric only. I have a 2010 Prius level 5 trim that just popped it's headgasket on its second engine at 431,000 miles. Rather than installing another JDM engine in a car with that many miles I replaced it with a Gen 4 Prius Prime. The EGR was redesigned in the Gen 4 and the EGR gas enters the intake manifold behind the throttle body instead of a tube with 4 rather tiny passages on each cylinder which tend to clog up and overheat cylinder 1 especially and lead to headgasket failure. I say hopefully it will last longer than the infamous headgasket blowing Gen 3. Other improvements in gen 4 1.8 liter are higher tension piston rings which reduces blow by which clogs up the intake manifold and blowby causes oil burning so hopefully your Prius Prime will longer than the Gen 3 Prius which is now not recommended to buy because known headgasket issues by several mechanics