[neilr]

Originally Posted by mav1178

There's simply not enough high-mileage FRS/86/BRZ documented among enthusiast circles to say "this engine has a similar head gasket problem like older Subaru engines".

Maybe a few years down the road, there will be some "a-ha" moment when some flaw in the FA20 is discovered from a longevity perspective. But there simply isn't enough high mileage cars to say whether the head gasket will just blow up after 100k or not.

The side discussion about coolant conditioners is more about previous engine design flaws and preventive maintenance when you change coolant.

Nissan had a "flaw" on the KA24DE for many years, where the upper timing chain guide will rattle and break off. For years, Nissan told techs to replace the tensioner and guides as a fix, since it tends to rattle because the chain is losing tension as the oil pump ages.

Then about 10 years after the KA24DE was introduced, Nissan updated their TSB to simply tell technicians to remove the guide and not bother with replacing it.

So to answer your question: no there is no known head gasket issue on this engine. Your wife's car's issue is irrelevant and unrelated and should not influence your buying decision.

-alex

Thank you for the longer explanation. Your previous post was unclear to me. :-)