What happens if you pour coke into the toilet?

Coke and other soda contain acids such as phosphoric or citric acid that give them a fizzy flavor.

These acids are slightly stronger than vinegar, strong enough to damage plumbing, fixtures, toilet flappers, wax rings, bolts, and seals over time; but a simple pour of a can or two of coke into the toilet bowl will most likely not cause immediate damage.