Head gasket leak may actually be coolant leak on Nissan Maxima

A coolant leak can develop from the front of the cylinder head that can appear to be a head gasket leak. There is a threaded plug just below the camshaft that may leak if there is corrosion present on the threads. Cleaning any residue, re-installing the plug with pipe thread (Teflon) tape, and torquing the plug to the specification typically repairs the leak.