We recently remodeled our powder room, and (after a great deal of research) installed a TOTO DARTMOUTH ((362-ST753S12 & 362-C754SF12)toilet. We changed the handle to an jJACLO oil-rubbed bronze (9141-ORB). At times, after flushing, the toilet continues to make a pulsating sound that lasts for a few seconds. It is not the "usual" sound that can be resolved by rattlling the handle. The sound will continue until the toilet is flushed again HOLDING THE HANDLE down longer.
After all my research to ensure we purchased a low-volume toilet that flushed well, I am somewhat dismayed that the toilet occasionally needs to be "re-flushed" after use to stop the "pulsating" sound.
We did not encounter this problem with the standard Toto handle that came with the toilet. It began when we installed a Moen handle to match our faucet. Replacing the MOEN handle with the JACLO handle the store suggested has not eliminated the problem.
Is the flapper chain to tight?
Often the fill valves pulse when the flapper is leaking.