I've been asked to explain why people say вешать лапшу на уши for uncovering lies and expressing distrust. Where does it come from?
The meaning is so because one cannot see the noodles on one's ears. One with noodles on the ears would seem funny to the surrounding people but he himself would not notice anything.
If I understand you correctly, you mean the Russian expression вешать лапшу на уши - "to tell lies, to give baloney to somebody".
As far as I can see, there are two things to be explained. First is why the verb is вешать - to hang. Second is why the word is лапша - noodles.
Internet search shows that the etymology of this phrase is unclear, and there are several versions.
None of the versions is reliable. I personally prefer the third one.