When to worry about engine noises?

TT5.9mag said

Oh yea I agree, I was paraphrasing the OP. Lots of people think that because it runs good it won’t have a problem and that can be very very deceptive.

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Don’t worry. I don’t think that the engine running well means all is ok…do I have to say this?

I wanted to clarify that there were no other obvious manifestations of the problem.

Thanks!