If you unplug the CSV and the rich condition abates (or changes in any way in August) replacing it will only be a waste of money and effort. The fact it is being turned on is the problem, and its response won't change if you replace it.

What turns it on is the computer's calculation of engine coolant temperature, and it should not turn it on until the temperature is below freezing. So, the fault is in the computer's determination of temperature, or more likely the sensor in the head or its wiring. If the sensor is open circuit, it will ask the computer to deliver full choke (in FI speak, long duration on the injectors) as well as turn on that valve you want to replace.

Meanwhile, before you figure out what is wrong with the ECT sensor, there's no downside to disconnecting the CSV. In fact, do it, so you don't continue to contaminate your oil with fuel. Then fix the sensor (or ECU or wiring) and change the oil as soon as you're done. Watch the temp gauge and see if the needle now runs where it should -- that measurement is separately made by the gauge sensor -- then determine whether you think the coolant thermostat is running open.
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Art Benstein near Baltimore

Show me a piano falling down a mine shaft, and I'll show you A-flat minor.