Put water, kielbasa, potatoes and cabbage in the Instant Pot. Make sure the contents don't go above the "Max Fill" line (if they do, remove some of the cabbage). Sprinkle with garlic powder.
Close the lid and turn the valve to a Sealing position. Press the "Pressure Cook" or "Manual" button and set the time to 10 minutes.
When the Instant Pot is done cooing, quick release (QR) the steam. Drain excess water, add salt and pepper to taste and serve.
Notes
You can make it with uncooked sausage - just add raw sausage links, increase the cooking time to 12 minutes, and slice the sausage after it's cooked.