What is causing air bubbles to come up in toilet and water to back up into bathtub?

There could be a blockage.. or possibly a hole in your water line causing air to be let in... could be one of many things... :(


See this post it may show some insight..

https://www.askmehelpdesk.com/plumbing/help-air-bubbles-coming-toilet-overflow-flush-occasionally-empties-11413.html

What is causing air bubbles to come up in toilet and water to back up into bathtub?

Forget the hole in the water line. If you had one it would spew water out not suck air in. You have a blockage in the toilet drain downstream from your bathtub. The drain needs to be snaked out. This can be done in one of several ways
1) you can pull the toilet and snake from there.
2) You can send a snake down the tub waste and overflow **OR**
3) you can snake from the lavatory roof vent.
If you snake from the roof put out enough snake to reach the base and 16 feet more. Good luck, Tom