355 Proper Cooling Fans operation

It is not really necessary to keep the coolant/engine temp no higher than 85C fully open thermostat but it should not be allowed to go too much above. Assuming that the coolant after rad is at about 5C lower than the engine temp, the 87/82 rad fan switch will come on at engine 92C and go off at engine 87C which is fairly close to the 85C of the thermostat. Then, if the car is moving, the thermostat will take-over from there. A 92/87 rad fan switch will start the fan at 97C engine and switch off at 92C engine, quite a bit above the thermostat's 85C but it is not really a big issue. No harm if the engine is running in the temp range 97-92 C when the car is stationary. So, it is more a matter of preference in which temp range one wants the engine to run during prolonged sitting/idling.

Another example - my 1998 Saab 9-5 (turbo) has a thermostat that is fully open at about 94C. The fans come on at 100C and go off at 96C which, again, is fairly close to the thermostat's 94C.

Position of the NTC and the rad fan switch:
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What I don't understand here is why your RH fan is coming on at 196F (91C). It's like the ECU is putting on the RH fan too early. If the scanner is showing what's coming out of the sensor, then there must be an ECU logic fault. I can't assume anything is good until you test those sensors. The only way this would make sense is if the scanner has lag and the temperatures were rising.
It's not like there is a faulty NTC sensor. The ECU should have the same NTC temperature data as the scanner.

 

The reason why the LH fan is cycling quickly could be simply because of cold weather which rapidly cools down the water in the radiator when the fan comes on. Anyhow, it is good to have this and the NTC sensor spare. If the LH rad is still cycling quickly when the weather gets warmer, you can put the new one in then.

A faulty NTC can affect the mixture in both ways depending on what the fault is - if it fails completely (open circuit), it will cause rich mixture (the ECU "thinks" the engine is at -273 C); if its temperature dependent resistance shifts and it starts showing lower resistances at temperatures, it will cause leaner mixture. Lower resistance than specified for a given temperature will make the ECU "think" that the engine is hotter than it actually is and it will lean-out the mixture. Your RH rad coming too early, earlier than LH fan which comes on at ~92C engine temp, matches this assumption (the cooking pan test of the NTC will tell you).

Until you perform the mentioned test, you can set aside the engine temp reading that the scanner showed. To more accurately monitor the water temp in the pan, I suggest you use a good quality multimeter which also has a Thermocouple probe (the cooking thermometers can be quite inaccurate).

 

I didn’t bother to look it up but basically it works as described above
I was giving you a quick response so you would understand the basic operation
Not an exact one
Use your Obd and read digitally will be better or if you want really exact install another calibrated thermometer I guess