I have 2 toilet in my house
When the upstairs one is flushed the down stairs one bubbles
Both flush fine
Good the vent be plugged
Have no smell from it

Please help

Does it "gurgle" or do you see "bubbles"? Let me know, Tom

Hi Mike...

Answer Tom's question, of course.

Then tell me if this is a new development or an ongoing issue? If new, then Tom is headed in the right direction, for sure. If this is an ongoing issue it could have something to do with the way the plumbing is piped up.

Anyway, let me know... O.K?

Mark

Does it "gurgle" or do you see "bubbles"? Let me know, Tom

It bubbles

You have a partial clog in the drainage line. Let me explain what's happening. You flush the upstairs john, The discharge picks up speed and bangs into the partial clog in the line and starts to rebound back pushing a bubble of air ahead of it. This is what you see in the f toilet. Then, because it's not completely blocked the discharge drains away before anything overflows. This can only get worse. The drainage line that services the toilet needs to be snaked out or if you're on a septic tank it should be checked to see if it needs to be pumped. Hope this helps and thank you for rating my reply. Tom