Are you sure it’s that and not possibly the water bypass o-ring?Man I have been searching for answers. My 04 IS has a leaking freezer plug. The first one on the passenger side underneath or near the water pump, I just did the WP and timing belt and valve cover gaskets all fresssh and can’t believe this one freezer plug is pissing coolant, can I replace all these plugs with the engine still in the car ?
double checked by spraying brake cleaner to remove oil and gunk Around the mani and wP and starter the car up let it warm up and it’s over 98 degrees where am at, all my Seals, o rings and coolant hoses are all new even the radiator. Put a twisty flashlight under the mani and sure enough notice some pooling around the lip of the plug and then once I turn the car off it started to spew from a very small pin hole. I’m sure it’s corroded from the inside, thought about sand paper and some Jb weld but I don’t like halfassing or using ”bandaids” unless for emergencies like getting home, crazy that a part that cost like 1 dollar literally might cost me a few hundred bucks in labor hahaha 😂Are you sure it’s that and not possibly the water bypass o-ring?