This goes for anyone with stand alones...at what coolant temps do you turn on and turn off your radiator fan(s)? I think mine turn on around 208 and off around 200, but I'm not sure if this is right. I have no idea what OEM ecu does either.

 

All the defualt MS users use 170 degrees farenheit. OE runs at 190 i believe but i could be wrong.

 

I have a 180 Thermostat, so around 190 for me

 

OE 1.6 comes on at 97c/207f, OE 1.8 NA 95c/203f.
I had my fan coming on at 93c (180f tstat) following the theory that it's easier to keep the coolant from getting hot vs. trying to cool down the hot coolant. But I bumped the on temp back up to the stock 97c because it was coming on all the time (and it's a loud spal straight blade). At 97c on it rarely comes on. There is definitely a plateau in the coolant temp rise after 93c with my car.

 

Stock ECU: Mine kick on at 180°, turn off around 175° (180° thermostat)

 

Then there is something wrong with your thermoswitch or the method you are using to read coolant temp. OE ecu on the 1.6 cars does not control the fan.

 

But remember, the temp at the thermoswitch is different than at the coolant temp sensor on the back of the engine.

 

NA 1.6, by the book, is supposed to turn on above 207 F(97C) and off below 194F(90C)

 

According to coolant temp at the t-stat housing thermoswitch. The coolant sensor at the back of the engine, which the ECU uses, may very well be reading something different, depending on cooling system health, etc.

 

yeah, I believe I'm reading temps from the sensor off the t-stat housing...so it will probably be lower than theromosensor readings. At least I know the t-stat is opening when it should

 

I'd be surprised you could get readings from that "sensor," seeing as it is just a thermoswitch

 

The link uses the OE temp sensor. With in a couple of degrees of 97* as indicated on the link I can hear the fan kick on.

 

Main fan comes on at 175F. So it stays on the whole time. A/C fan runs off the thermoswitch which switches at 206/207.

One of my future projects is to grab the VSS signal from the cluster to interrupt the fan circuit over a certain speed. That's way down on the list though. I was also going to try to remove the a/c side fan, just to see what happens.

 

I like that; that's good news.