One toilet got flushed with too much paper in it. It was slow then it seemed to fix itself but there was an interaction between the two toilets in the house now. The water levels change on their own and make an air burping noise. The one that originally got the clog flushes well the second toilet has been a slow non-forceful flushing toilet for years.

What the problem seems to between the line connecting the two toilets at this time.

Are the toilets back to back, that is in separate rooms? If you are gurgling through the toilet, that is usually an indication that a vent line is restricted. Instead of allowing air in as the water flows through, the toilet is trying to pull or push air out and through the other toilet. Have a plumber snake out the vent lines to see if twig or leaves may have fallen down and got caught at an elbow. You may also have an obstruction in the drain line that is slowing down the draining of the other toilet.

The problem is that the clog moved downstream. Have the drains augered with a drain/sewer machine and lots of water flushed through to be sure the clog is not just moving further down the pipes. The vent is okay, the gurgling you hear is the bottlenecking of water and air due to the clog, then the air being pushed back up the pipe.

I always caution that running a cable down a vent could cause more problems that are solved. Large chunks of scale breaking loose and falling into the drain or losing a cable in a stack. Both usually are remedied by cutting open walls and stacks.

Hi Guys:

Yeah, snaking down a vent is something I don't ever recommend but that may be because most of the homes in my area are 2-3 or even 4-5 stories on average. Tom (speedball1) likes to recommend snaking down the vent, but that is because he is in Florida and almost all homes are flat roofed and single story... ;)

In this case, I believe the clog may have moved into the branch for the second toilet and could be causing your issue. Here, if the toilets are close to each other, you could purchase a CLOSET AUGER tool (see image) and try to snake through the both toilet trapways and see if things are improved. If that fails to fix the issue then you may need to lift one of the toilets and snake the drain line itself using a medium cable machine as PGHplumber recommended.

With all that being said, I'm curious about the fact that the second toilet has been a " slow non-forceful flushing toilet for years". And now you have this issue, too, right? Snake the toilet using the closet auger and then check the water level in the toilet tank.. should be an inch below the overflow tube. Also, check to see if the refill tube is fit into the overflow tube... pretty important to a good flush.

Finally, as asked by Ma0641, are the toilets back to back, or how far apart are they? Also, is this a one piece toilet or a two-piece toilet? Let us know more, OK?

Mark