My son has a juul and I put vinegar in it.
What on earth motivated you to put vinegar in his juul?
I wanted him to stop smoking e-cigarettes.
That's harmful and reflects badly on your parenting. There are other ways to get your son to stop vaping that won't harm him. Maybe you can have a conversation with him about your wishes.
Maybe, but I bet he feels bad about it.
I'm quite sure it was an unpleasant experience for your son and you shouldn't be sneaking anything into his juul without him knowing. Not only is it immoral but it could also harm him. You should be more mature in the future and talk out your issues rather than going behind his back.