Is it true that you can use Coca Cola to clean pipes?

I don't think so if coca cola could help. Alternatively you can use bleach, it should remove all oils. If that is not helping you can use drain unblocker, but you need to be careful because it is acid based and you need to read directions to use first

Coca Cola will only clean the tarnish off certain metals, example being if you put a one pence coin in a glass of coke overnight it will come out shiny after a few hours soaking. It won’t clear your drain.

Coca Cola can be used to clean certain metals and make them look nice and shiny again (purely cosmetic) but first off you have to soak in Coca Cola a quick wipe won’t do much as for the sink in your kitchen it sounds like it is blocked so the blockage will need to be cleared, it might just be a small blockage in your trap which is a very simple fix or it could be further down which could be a bigger job unfortunately.

hi, best to remove trap and take a look , if not happy removing it yourself call a plumber ,thks