![Toilet makes hissing sound unless I open the back and press the black piece, which seems to release air and stop the hissing. Any suggestions? : r/fixit Toilet makes hissing sound unless I open the back and press the black piece, which seems to release air and stop the hissing. Any suggestions? : r/fixit](https://external-preview.redd.it/yoWsRVLlXRCKG1ty5--BmtYamy9C4Mk_pFcTX_lBfjk.jpg?auto=webp&s=ae0b9e14cfc3f4a4dccdbf15ecf7cd8cc9cc4b4e)
Toilet makes hissing sound unless I open the back and press the black piece, which seems to release air and stop the hissing. Any suggestions? : r/fixit
![How to Determine What a Toilet Noise Is | Toilet Making Abnormal Noise | Toilet is Loud | Fluidmaster How to Determine What a Toilet Noise Is | Toilet Making Abnormal Noise | Toilet is Loud | Fluidmaster](https://www.fluidmaster.com/wp-content/uploads/2016/11/determine_article_photo.jpg)
How to Determine What a Toilet Noise Is | Toilet Making Abnormal Noise | Toilet is Loud | Fluidmaster
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