Inside a worn garbage disposal: rusty grinding plate and lugs seen from the sink

Water spurts from the dishwasher air gap at the sink (blocked disposal inlet, knockout plug, hose)

The air gap is doing its job: when the path from the air gap to the disposal or sink tailpiece is blocked, the water exits at the sink instead of flowing back into the dishwasher. The blockage is almost always downstream: a knockout plug never removed from a new disposal's dishwasher inlet, food packed in the disposal inlet or the hose, a kinked or collapsed hose, or debris inside the air gap itself.

Cross-checked ~30 min easyBrands: All

Before you start

Turn off and unplug the disposal (or switch off its breaker) before reaching into it or working on its inlet
Never put a hand in the disposal; retrieve the knockout plug with pliers or tongs
Use hose clamps rated for the job; overtightening can crush the hose nipple

Diagnostic steps

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