#gasket

We had two updates to a previous Piston Slap this weekend, surprisingly within two hours of each other. Let’s hear from the OP first:

TTAC Commentator sundvl76 writes:

Sajeev, reporting back:

You may be interested in this, if for no other reason than to add to your diagnostic toolbox; my experience certainly can’t be unique: Several comments below your post also suggested the motor mount(s) as the problem. I more recently discussed this with a professional wrench acquaintance, who also said that the mounts can be expected to go south after ~80K miles; he suggested using a padded floor jack to lift slightly on the engine during a time when I detected the “rough” idle (the oil pan on this vehicle, and maybe all Duratec engines, is waffled cast aluminum). Bingo! The vibration ceased when I did that.