What would cause the low engine coolant light to stay on when the coolant isn't low?
You could have a bad sensor, a bad wire or a bad wire connection in that circuit. Check for voltage to sensor and after sensor. Check wire connection on sensor.
the float is stuck in the resivoir.
On 2001 Impala LS the Coolant level sensor located on the radiator just behind the battery. Go to OE Warehouse.com use AC Delco #10096163 and get it cheap for $26.05 the exact OE sensor in your car now... Auto parts stores are asking $59.
How long it takes to get fix
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