What does po116 mean in diagnostic codes?

Ray Komar, the P0116 code on the VW means that there are issues with the " Engine coolant temp circ. range/performance Coolant"

Possible causes

- Low engine coolant level

- Faulty Engine Coolant Temperature (ECT) sensor

- Faulty engine coolant thermostat

- Engine Coolant Temperature (ECT) sensor harness is open or shorted

- Engine Coolant Temperature (ECT) sensor circuit poor electrical connection

Coolant temperature signal sent to the engine Control Module (ECM) is not within specified range.

Symptoms

- Engine Light ON (or Service Engine Soon Warning Light)

P0116 Volkswagen Description

The Engine Coolant Temperature (ECT) sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the Engine Control Module (ECM). The modified signal returns to the ECM as the engine coolant temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases. from here

It is most likely that the Temperature Sensor (ECT) is failing and/or a new water pump is needed. Hope this helps, good luck.