My toilet won't fill when I flush it. However, I've noticed that if I turn on the bathtub water right next to it, and then turn it off, the toilet will start filling. Strange. My water pressure is generally good throughout the house.
Any ideas on this one? Bad flex lead coming into the toilet? Bad fill valve? Slow pipes in the walls? The pipes are about 70 years old.
Sopunds like you may have some trash in the fill valve or the toilet supply valve. Turn off the water supply valve and disconnect the tube going to the toilet. Hold a rag over the valve and quickly turn it on and off a couple times. This should clear the valve. I would change out the fill valve since for under $10 you can install a Fluidmaster 400A valve. The trash may be bolcking the flow of water until you use another fixture (tub) and the trash "relaxes" some, allowing water to flow past it.
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