Hi guys I have a Mazda 5 2010 and I found engine coolant in the ignition coil housing, the coolant is not in the combustion chamber. Somehow I'm thinking the coolant is leaking through the intake manifold or exhaust gasket and making its way through the engine head and getting into the spark plug/ignition coil housing (Cylinder 1). Anyone can confirm this theory for me please?

I did a coolant pressure test. It's not holding pressure but no visible leaks were found.

Thank you!

 

I’m pretty sure as engine is Ford based there are coolant core plugs between 1-2 and 3-4 plugs. On fords these leak very common but only seen it on the smaller engines. Pull out the coils and have a look at an angle down plug holes to try find out. If it is these it’s cam cover off and get them replaced. Not a huge job