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Car overheated on highway just now, I'm still out here...

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racer47

Still winning after 30+ years
392
497
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W2W Racing
Exp. Level
20+ Years
SE WI
Since you have a handheld tuner, you can check to see is Lund left the fields open (some do, some don't). Just go in and reload the same tune that is currently in the car. As part of that you can step through the low speed fan on, high speed fan on, rear gear ratio, tire counts and 1 or 2 other things. If there are no options available, then you need to ask for a copy of that same tune with the field left open.
 
1,246
1,243
In the V6L
The contact spacing is sufficient for several hundred volts, so a 12 volt system can't create a voltage flash-over type of arc. 30 amps through a corroded connection can sure get hot though.
 
598
536
I know the low speed on a 2011 comes on at 205, thats what the IDS at ford showed as the tech and I where checking it.
It never got to high speed, No AC.
 

xr7

TMO Addict?
706
821
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Autocross
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10-20 Years
Minnesota
Some of the wiring is barely adequate for the job. Throwing a higher load on the system makes it worse.
Up here in the frozen north it is a common problem with heater motor circuits. Lots of melted connectors and fried wiring. Also check and see if the motor is drawing more than it should. You are on the right track but upgrading connectors, wire size and wire quality.
 

Grant 302

basic and well known psychic
It seems this problem has existed for a while in the SN95 cars, and still exists in the S197 cars. Some people have luck just replacing the fan resistor, some have luck adding dielectric grease, some have luck doing a combination of dielectric grease, wire brushing contacts, squeezing contacts to mate tighter etc. etc.

I think you'd be on the right track here. Improving the contact at the pigtail and reducing resistance should help keep the heat in the resistor/heat sink assembly. A bad connection would prevent the heat sink from doing its job.

I've had 3 SN95s and two S197s and never experienced this even with heavy use of a fan bypass circuit on the drag car. So I doubt the issue is in any tune and the commanded temps.
 
understood, but from what I have read tuners (such as lund) by default move the fan on and off temps to a lower than factory temp as a safety thing. I would like to have my fan come on and off at the factory settings because I am using a factory ford thermostat.
 
Never found the factory fan settings, and my SCT X4 does not allow me to change that anyways...

Today i received my new ford plug and new contacts. De-pinned the melted plug, pinned out the new plug. I also squeezed the female spade contacts to make a 100% positive connection with the fan resistor contacts. Added a little dielectric grease for good measure.

The new plug, squeezed contacts, dielectric grease, and the upgraded wiring and terminations of the resistor harness all seem to be working.

I let the engine idle until it got to operating temperature. At 184°F the low speed cooling fan came on. It stayed on at 190°F when i took it for a ride and ran though the gears to create some heat.

Pulled back in the driveway and max temp was 196°F, and the high speed fan was on.

I guess everything is working. I wish i knew the oem fan settings.

Ill play with the car some more tomorrow after work.
 

racer47

Still winning after 30+ years
392
497
Exp. Type
W2W Racing
Exp. Level
20+ Years
SE WI
Those fan turn on temps are way lower than stock. I don't remember what my stock fan settings were but its something like 200 F low and 215 F high. Search s197forum for the stock temps. The factory runs it hot for emissions. Most tuners turn them down to something like you have now. Also, its not the X4 that doesn't allow fan changed. Its a setting in the tune file that either allows or blocks you from changing anything.
 
Don't you two have different motors?

My Boss ran at 196 regularly on the street.
 
Those fan turn on temps are way lower than stock. I don't remember what my stock fan settings were but its something like 200 F low and 215 F high. Search s197forum for the stock temps. The factory runs it hot for emissions. Most tuners turn them down to something like you have now. Also, its not the X4 that doesn't allow fan changed. Its a setting in the tune file that either allows or blocks you from changing anything.

I know Lund has disabled my ability to adjust the fan settings in the X4. I have searched multiple forums, and have yet to find actual OEM fan settings. I typically find suggested, or "current tune settings".

I will have to email Lund and ask them to adjust my tune to allow Fan setting adjustment if I feel the need to do that, and set the fan back to OE settings.
 
Drove the car to work today. At 5:30am it was 78*F and dark.

The coolant temp peaked at 196.42*F during the 25mile trip to work. Everything including the fan seems to be working fine with the updated wiring, improved terminations, and a new (un melted) plug with a little dielectric grease for good measure. The high speed fan was on when I parked the car which was a good sign.

The real test will be on the way home today at 3pm when it should be about 105*F and sunny.

I hate these kinds of issues because now I have to re-establish confidence in my cooling system. Its also one of those issues that will also cost my bank account a coolant temp gauge, ford performance triple gauge pod for the dash, an oil pressure gauge, and an oil temp gauge....
 
So after a week of driving to and from work. 80°F in the morning on average, and 105°F in the afternoon average. The car rarely goes above 197°F

I have re-gained confidence in my cooling system, but will be adding a water temp gauge.
 

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