I have the exact same, but on the front.
I have replaced/swapped spark plugs, coils and injectors.
The front three plugs are sooty, thus also the oxygen sensor in front has been replaced. Still have to check continuity to the brain.
So far no luck.
It could to be a water leak from the inlet manifold to the inlet valves on either corner cylinder, as water is in close proximity to the inlet, and over pressure on the water side is combined with vacuum on the gas side makes the water travel through the gasket.
The last can be checked by checking for water on the spark plug.
Normally is will just be a cough or two on start, and would quickly burn off.
Read the codes if you have a code reader. My yellow engine light is also on. Brian tells me that it takes 40 good cycles to switch off by itself.
If you don't get it, Marinabrian is your man.
Let me know if you find it!!
I am still searching!
