100% Cooling Fan Turn-On Temp

[galaxy]

Anyone happen to know the temp that the cooling fans kick up to 100%?

Was just recently noticing I never hear mine run at 100%. They work as I’ve heard them kick to 100% with the A/C on or if I crank the car back up when it’s hot outside and it didn’t sit long enough to cool off. But during driving, slow traffic, parking, etc, it never does. I’ve seen CHT get to 223° and then it’ll start coming back down, but the fans are doing that at the 40%.

Yes, I know this isn’t too hot and things are working. Just curious the number. Getting ready to order tune and would be a perfect time to drop the 100% setting down to 220° or so. Keep things just a tad more under control, ya known.

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[K4fxd]

Looks like 223 for 100%

212 for 40% turn on

 

[Bullittproof]

I am not used to vehicles with electric cooling fans, I have never parked my 2023 5.0 and heard the fan still running as I walked away (as I have observed vehicles doing in parking lots). Does the GT not do that or have my cooling needs always been met?

 

[ice445]

I am not used to vehicles with electric cooling fans, I have never parked my 2023 5.0 and heard the fan still running as I walked away (as I have observed vehicles doing in parking lots). Does the GT not do that or have my cooling needs always been met?

They don't do it in my experience unless it's way hot, like above 240 maybe? I've never seen it. But yeah, low speed is 210 coolant temp and high speed is 223. There's also the grille shutters to account for. They open more progressively as you get to that 223 number. Or if ambient or speed is above a certain number they will also open/behave differently.

 

[Bullittproof]

Thanks ICE445, this topic is something I had not even thought about until the original question was posted.

 

[Skye]

https://www.mustang6g.com/forums/threads/radiator-fan-temperature.165260/

The attached, by @EFI.

 

[Bullittproof]

Thanks for the link, Skye.

 

[JAJ]

Anyone happen to know the temp that the cooling fans kick up to 100%?

Was just recently noticing I never hear mine run at 100%. They work as I’ve heard them kick to 100% with the A/C on or if I crank the car back up when it’s hot outside and it didn’t sit long enough to cool off. But during driving, slow traffic, parking, etc, it never does. I’ve seen CHT get to 223° and then it’ll start coming back down, but the fans are doing that at the 40%.

Yes, I know this isn’t too hot and things are working. Just curious the number. Getting ready to order tune and would be a perfect time to drop the 100% setting down to 220° or so. Keep things just a tad more under control, ya known.

There are two tables that control the fan. One is coolant temp, and the GT350 uses the same table as the GT as shown in this thread.

The second table controls the fan when the AC is on. It's dependent on external temp and the pressure in the AC system. It's not a function of engine temp, it's purely to make sure the AC keeps delivering coolness.

As for dropping the 223 degree limit, I don't see the point. When the car's moving the fan doesn't matter, and when it's not moving, a couple of degrees don't matter.

 

[galaxy]

There are two tables that control the fan. One is coolant temp, and the GT350 uses the same table as the GT as shown in this thread.

The second table controls the fan when the AC is on. It's dependent on external temp and the pressure in the AC system. It's not a function of engine temp, it's purely to make sure the AC keeps delivering coolness.

As for dropping the 223 degree limit, I don't see the point. When the car's moving the fan doesn't matter, and when it's not moving, a couple of degrees don't matter.

Yeeeahhh, after talking it out, I tend to agree.

Is there logic built into the fan that prevents the fans from running while driving, say, above a certain speed? Just curious. Or the same temp table applies regardless of speed?

 

[galaxy]

Not sure how accurate that table is or if something else is afoot. Was out running some errands today. 85° and stop light traffic around town. I hit 223° several times and it creeped up to 225° on three occasions and the fans never once went to 100%.

But I know the 100% works because it’s coming on with the air, and if I shut the engine down for a very short period to run in the store, come back out while it’s still heat soaked, when I crank it up, it goes straight to 100% and that kicks off about 225° the once or twice I was able to catch it.

 

[EFI]

Not sure how accurate that table is or if something else is afoot. Was out running some errands today. 85° and stop light traffic around town. I hit 223° several times and it creeped up to 225° on three occasions and the fans never once went to 100%.

Those are set based on ECT (engine coolant temp), what you're seeing in the dash is CHT (cylinder head temp).

The CHT is generally 8-10* hotter than ECT, so you should add that into the calculation when referencing the tables. Although I believe ECT is calculated with a few different other factors, so it will never be exact when looking at CHT. Dunno why they did it that way.

 

[galaxy]

@EFI Aahhhhhhh snap...I knew that. Dang it! Thanks bro.

So now that all makes me think my Mishi radiator is doing a better job than I thought it was. I thought something was wrong when I first put this thing because my CHT's were different (I should have taken better notes), but my fan used to turn on 100% more often. Like stated above, my fan darn near never goes to 100% after the radiator install.

I think it's time to step away from the keyboard and stop worrying about s$%&, LOL.

 

[honeybadger]

Those are set based on ECT (engine coolant temp), what you're seeing in the dash is CHT (cylinder head temp).

The CHT is generally 8-10* cooler than ECT, so you should add those into the calculation when referencing the tables. Although I believe ECT is calculated with a few different other factors, so it will never be exact when looking at CHT. Dunno why they did it that way.

Are you sure about that? CHT is an infrared sensor in the head itself right behind the hottest part of the passenger head (cylinder #4). I understand I have a modified cooling setup, but I have separate sensors for each and my CHTs typically run 15-25 degrees hotter than my water temp (CHTs raise after extended WOT and cool back down after 10 seconds or so).

 

[galaxy]

@honeybadger Im gonna go out on a limb and think he meant to say hotter. I think that’s common knowledge. His post reads like (or such I took it as) that’s what he meant. But he can clarify.

 

[JAJ]

According to my 2016 wiring diagram for the GT350, there are only two cooling and lubrication system sensors on the engine - CHT and Oil Pressure. EOT and ECT are both estimates computed from CHT so don't expect precision.

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