Hello all, I have an f150 2004 4.6, I recently had to replace a coil pack and a spark plug on it, then another went out, so I bought another coil pack and plug, but when the mechanic went to replace it, the spark plug well had antifreeze in it, what could be the problem.

 

Which plug and is it a heritage?

 

It is either the 5 or 6

 

Could be the crossover in the front on the intake. If not, then the aluminum head could be cracked. I'm thinking it is probably #5 which is the front plug on the passenger side and either the coolant crossover is leaking or the gaskets on the end where it meets the head is leaking.

 

Yep, was hoping you'd say #4, that is a much easier fix.