cylinder head coolant leak

[CnlK]

Believe the owner's manual states that spark plugs are good for 100k, don't like to leave them in that long so I replaced them @ 84k. While dry at the time, there was evidence of a slight coolant leak near #2 & #3 cylinder spark plug wells. There is a cylinder head temp sensor located between these cylinders. Pulled it thinking is was the obvious source and found that sensor protrudes into a dry well. Anybody have any thoughts, does rocker cover gasket seal any coolant passages? Car doesn't use much coolant, if reservior is at full cold mark it will lose about 3/4" and stay at that level. Thanks for any suggestions, did put a little sealer on temp sender threads.
2007 2.3L 4cyl.

[danielsatur]

You might consider www.steelseal.com , or www.gobluedevil.com

[CnlK]

Thanks for the links, don't think it is a head gasket leak as traces of dried coolant are above that point. Plan on pulling the #2 spark plug coil/boot and looking in there again. The ends of the plugs and piston tops all looked good and no sign of coolant in the engine oil. Of course suppose there could be porosity or a crack in the head itself. (Pulled #2 boot/coil and looked at top of head after several days,
surface was dry)