Toilets, Sinks, Showers, Tubs and Disposals - toilet run-ons all by themselves

We have replaced our toilets but now, after the flush is complete & toilet is completely stopped, every few minutes they start making the run on noises like you need to jiggle the handle. They do this off & on all day long. What could be wrong? We have two full baths upstairs, one downstairs and a half bath on top of the slab with the disposal type flush system. When we use the half bath sink, it makes the disposal noise at the toilet next to it. I figured that was just a fluke of having an above ground system. We are on septic tank system. It's driving me nuts. We have a water shortage & I really hate hearing these two toilets upstairs just come on & run by themselves. HELP!

Plumbing pros will probably check in shortly. In the mean time,have you checked the tanks on the back of the toilets to see how full they are? You may simply need to adjust the float level screw or bend the float arm slightly to have the toilet stop before the water reaches the overflow. You might also check the dump valve at the base of the overflow to see that it is seating properly and does not have water scale buildup.

The half bath sink will cause the pump to come on, just like flushing the toilet does.

First thing to do is isolate which toilet is the problem. Shut off one toilet at a time until the problem stops. Try that first and get back to me.