Coolant leak-misfire cylinder 6

Hi. Has anyone else had a similar issue? Misfire code last week, running rough. Pulled coil and found coolant in the plug well and at the top where the coil seal is.
Dealer performed pressure test-passed (which I’m skeptical of)and cannot determine cause. Certified preowned purchased 4 years ago, still under powertrain warranty. 83,000 miles. Thanks

 

There is no possible way that coolant can get into a spark plug tube unless there is an external leak to the degree that it gets past the coil. Since it's cylinder #6, I would be inspecting the lines to the heater core in that area...

 

Thank you Tailhook. I will inspect those lines. That could explain why it passed the pressure test, if the valve to the heater core was closed.

 

I am pretty sure Tacomas do not have a valve and coolant runs to the heater core always.

 

What color is the coolant? That doesn't look like Toyota coolant if it's not pink or leaves a crust if it's been leaking awhile.