Lincoln LS - 2002 V8 - Overheating?

We have a 2002 Lincoln LS V8 that is either actually overheating or just saying it’s overheating.



Last year, the temperature gauge began to spike up to the MAX suddenly. This happened soon after driving the car from a cold start, or after driving the car at highway speeds for a period of time (e.g., 1 hour).



In both scenarios, if we pulled over and shut-off the car for a few minutes (e.g., 5 mins) and restarted the car, the gauge would show the temperature in the normal range. Sometimes the temperature would remain in the normal range for the remainder of the trip. At other times, the gauge would rise above normal again.



If we didn’t pull over and shut-off the car, the car would typically go into “protect mode” and automatically limit engine RPMs to avoid damaging the engine. At this point, the “check engine” warning illuminated and remained ON.



The overheating incidents started as an intermittent event, but became much more frequent - sometimes daily.



We had the following replaced in 09/2009:

- Water Pump

- Thermostat

- Coolant

- Hydrolic Fan Pump Acutator



The repairs seemed to fix the problem, but gradually, the problem returned. It’s odd, but We can hear the fan running when the car indicates that it is overheating.



Please advise. Please!

You need to have a good independent mechanic check your temperature sensor. If it goes bad it can cause all kinds of false warnings/overheat conditions. It seems to be the only link you have overlooked. I would have it replaced.

Agree - that to me sounds like classic behavior for a bad sensor. The part is cheap - $15 for a decent aftermarket, $35 for a Ford part. Replacement is easy - $35 labor tops.

The other possibility I could see is that the there’s air in the coolant system. I’ve heard (no idea if it is true) that these were not easy to bleed all the air out of, and I’ve even heard that the LS had a bleeder for the cylinder head near the master cylinder to help get the air out. I have NO idea if that is true - I’ve never heard of it before or on any other car.

Consider the possibility of a leaking coolant tank. Even the smallest of leaks on this oddball part can cause overheating.

My son and his wife owned an LS that had the same symptoms and this car even baffled me a bit at first look because, in theory anyway, a tank with a slight leak should not cause overheating unless the coolant level drops too low. In this case, not.

You will also notice the tank is buried big time inside the left front fender and it’s just about impossible to see any leaks.
This may not be the problem at all; just pointing out a real oddity on these cars.

No, for the LS this is the classic symptom of real overheating due to leaks in the degas tank. That lets air in, and the air pockets cause the heads to go over-temperature. The gauge on the dash normally displays water temperature. When one of the heads overheats, the computer orders the gauge to go to the maximum temperature reading.
The degas tank (and other plastic cooling system parts) only seem to last six to seven years. The cracks that form are too small to easily see, and often don’t leak enough coolant to notice.

I’d had the same experience, and have heard from many others that have as well.

HERE’S A SOLUTION…an independent mechanic disabled the hydrolic cooling fan and replaced it with an electric cooling fan. The overheating problem has NOT resurfaced - it’s been about a month so far.

So i have a 2004 Lincoln ls that has a bad overheating problem. I have replaced the thermostat but started overheating again just days later. So now im lost i dont know how to fix it. Please help!!