I have lived in this house for 5 years and I have a 1.6 gpf toilet. Since I first moved in, it has not flushed consistently. One time it flushes just fine...the next time it does not. It does not seem to matter how much of a "payload" there is in the toilet when it is flushed. The tanks refills properly and empties like it should. When the first flush does not empty fully and it is necessary to give it a second flush, often times the second flush just swirls around but does not go down. Often a third flush is necessary. It is just puzzling why it flushes correctly one time and does not the next.
Any thoughts / suggestions are much appreciated.