I have an '11 Crown Vic (270k miles) with an overheating problem that I believe is being caused by the rad fan not turning. Here's what I've seen so far...
1 - The overheat condition doesn't happen while moving, it only happens while in park after idling for a while
2 - Top radiator hose DOES get hot
3 - If the a/c is off, the rad fan DOES NOT turn at all during overheating as the temp gauge moves all the way up
4 - At normal engine temp the rad fan DOES turn as soon as the a/c is turned on, but I've only observed this so far at normal temperatures.
5 - During the times it overheats and the a/c is on, the cabin vent air gets hot and humid right when the overheating occurs. I haven't yet made it a point to check the rad fan at this point to see if it's still turning.
6 - During testing, after getting the engine temp up to idle hot and the temp gauge read normal in the middle, to trigger it to overheat I had to run the engine at 2k rpm for over 5 mins before the dash temp gauge began to rise. After the gauge begins to creep up I've let off the gas but the temp continues to go all the way up. Although to trigger the overheat condition I ran it at 2k for a while, it DOES overheat by simply sitting in park and idling.
7 - The coolant reservoir cap has a small leak but I don't think this is a major factor. I've continued to top off the reservoir throughout my testing and overall there doesn't seem to be much coolant leaking from the reservoir. Although, you CAN hear air seep from the reservoir cap when you squeeze the top rad hose.
The main problem seems to be the rad fan not turning. Any ideas? I'm all ears.
Edited by bradleyheathhays, 09 September 2018 - 04:48 AM.