Overheating message

[TobyU]

I think the limp feature isn't perfect. My 2000 V-10 went into limp mode, it wasn't even hot, and the gauge went from 3/8 max to pegged instantly. I put a Motorcraft thermostat in it, it has been fine ever since, and that was 6 years ago.

I would surmise that your thermostat was stuck and it was actually hot just up in the intake or the sensor is.
So it seems like it was doing his job correctly. I have run and serviced fleets of town cars and a good number of Ford trucks over the past 26 years.
I can remember one or two that had a thermostat stuck or sticking that the problem was totally fixed by new thermostat. I can remember another 96 Town Car that would overheat only when you accelerated. If you got it to speed quickly and coasted and maintain speed on flat ground it would not overheat. Even in stop-and-go traffic it would approach hot until you got up to around 42 miles per hour and coasted. This was a mostly restricted radiator because the radiator is in the Town Cars was not much better than adequate. This one was going into failsafe mode and canceling cylinders.
Put a new radiator in it and it was perfect for almost four years to the day. Then it started doing it again. Warrantied out the radiator at AutoZone and it was fine again.

Had another 92 that was starting to just get a notch or two above where it normally ran and mostly when an idled.
Found out this was also a partially restricted radiator. When it got up to temperature and the top hose was under pressure you could squeeze the hose and if you read it up it would forcibly open the house back up. If you didn't squeeze the host you could feel increasing pressure. It was only a few steps away from bursting a hose.
The pressure and flow from the water pump couldn't get through the radiator and was deadheading and building up pressure in the top hose.
I can't remember now if I was able to backflush that one and get the pressure to be normal or if I had to replace the radiator. That was before 2004.

Every other one that ever overheated was due to lack of coolant or coolant leaks from ruptured hoses or leaks or split intakes before they were replaced with the improved aluminum crossover one.

Quite rare to have failsafe mode problems with one of the older ones but it's a nice feature and I'm glad to have it.

 

[07navi]

Ya, I like that feature too, it could save an engine plus it doesn't strand you. Mine did go off again when I tried another thermostat to get the heater working faster but it didn't like it when I made a trip in 100* weather. I wish I never made that little "improvement' now. It kept limping and I kept waiting for it to cool down and it took forever to get home. I completely flush my system every 2 years now and I get the antifreeze from garage sales for peanuts. I run the flush/cleaner first for a week with just water first and have a way of flushing I invented that gets everything out.