where is low coolant sensor on 2000 buick regal 3.8

On the passenger's side of the radiator. A few inches below the radiator filler neck you'll see a little black square thing with an electrical plug on it. That's the coolant level sensor. It's held in place by a wire clip. If your coolant is dirty, flush the cooling system before you replace the sensor. Then expect the low coolant light to be on for a few days. This is normal. One other thing, if you recently had the radiator replaced and the low coolant light has been on make sure the hole in the radiator for the sensor is open so the sensor is in contact with the coolant. On some aftermarket radiators you have to drill out the hole. If you don't the sensor will be dry and the light will stay on. Hope that helps! Jim

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