^ lol you have carbon build up! ... there is nothing on the market for any direct injection engine that fix the problem of deposit and accumulation of carbon on the valves. You can slow the process by adding a catch can, oil additive, seafoam, water meth... etc
the process:
-X \hrs to remove the intake manifold
- let the bg chemical soak in
-0.5\hrs per cylinder to remove the gunk with a brush (manual scrubbing)
-X\hrs to reinstall the intake
-oil change
-coolant flush
Toyota is working\using a dual injection system which will solve the issue\ JHM motosport is testing the carbonator which consist of an additional subaru low-flow injector positionned
between the throttle body and the intake manifold..