Cooling Fans

[ChaosXIII]

During my last race I was plagued by overheating issues on my 2003 Focus 2.3l. Now I am trying to cover all my bases for the cause so that this does not happen again. Two stages into the rally my temps sky rocketed and I had to back off and run the heater. I ended up missing two stages while the car cooled down and to let the coolant stop boiling. After I finished the race it seemed like my expansion tank had a leak in it. So I changed that, then for peace of mind I changed the water pump, and flushed the radiator out, and installed a heat extraction vent in the hood. While I was down in that area I removed the whole AC system.

Everything seems okay for now. But after thinking about it I can not remember the fans kicking on at all during the race. I can power the fans directly and they turn on when jumping the fan to the battery. but after driving it around and trying to get them to turn on I have not seen them on. I am not overheating during normal driving, but I'm afraid it will overheat during a race. I have read that you can get the fans to go on by turning on the AC button and the re circulation button. But the fans do not turn on. But I have also deleted what I could from the AC system so i'm not sure if it would still function like that. Does anyone know what I should check first? I at least know that the fans can turn on.

 

[Tom]

If you let your car idle for long periods of time does the fan ever kick on? The only thing I can think worth checking and/or replacing is the fan resistor. I had to replace mine on my old Focus.

 

[ChaosXIII]

I let the car idle for a long time and I never saw the fan come on. I did some data logging on the car while driving it with a bluetooth obd2 reader. The reading seem like they're way too high. At one point in the log the PID named [FORD] Cylinder Head Temperature reported 271 degrees F and the PID named Engine Coolant Temperature reported 213 degrees F. However the temperature gauge on my cluster did not move from the middle. I checked the temperatures against the Odometer test mode read out and they matched what the computer was reporting. And this was when the car was at 25 mph. Those seem way too high. So it seems like my fans don't work and theres some other issues. Can anyone make any sense of this data?

 

[Tom]

Hopefully [MENTION=63]1turbofocus[/MENTION] can shed some light on this.

However did you replace the fan resistor and checked the plug to see if it corroded?

 

[1turbofocus]

All stock the Duratec Fans on Avg dont come on till (low) 218 , (High) 230 only way to lower these is with a tune

There are a few things that can cause engine over heating
Modded parts and no tune , causing to much/little timing , running lean
Thermostat it should have a 180 Deg
Dirty Radiator / cooling system
Water pump
Cracked Head
Blown Head Gasket

If you can give me some more info about what all you have done I will be glad to try to help

Tom

 

[ChaosXIII]

Hey Tom, after thinking a lot more about it I think the primary cause of the overheating during the race was the crack in my expansion tank that puked some fluid. I did not know that those were the temps that the fans came on. Its been cold out so its likely that it hasnt been getting into the range where the fans would be needed. And when they do come on compared to all the other noises of being in a fully stripped car drown out the fan noise. From what I can tell my low speed and high speed fans work when i jump the pins in the fuse box and and I have tested the relays so I may just be being paranoid. I thought the temps I was seeing were too high.
I am going to be swapping to a 180 Deg thermostat. I am getting the funds together to get the tune from you. Currently the engine is a 2.3l with an fswerks race exhaust and a steeda cold air intake.

 

[1turbofocus]

With a tune we can lower the fans and check everything else with data logging , I would also plan on a wide band o2 Air Fuel Gauge

Tom