Ford Fusion Coolant Temperature

We were cruising down the freeway in my wife’s 2014 Ford Fusion and suddenly got a dash notification that the engine coolant was over temperature. Sure enough, the gauge confirmed that the coolant temperature was over. We slowed down and started looking for a place to stop, and within seconds the gauge went back down to normal temps. The needle would move a bit toward hot, but each time would drop back down almost immediately. The heat blowing out of the vents has been ice cold. Could it be an electrical issue, or are we likely looking at a coolant leak/issue with the pump?

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First thing is to check the coolant level after the car has completely cooled off.
“The heat blowing out of the vents has been ice cold”. By this phrasing I assume you had the heat on rather than the AC. Therefore seems you have air in the cooling system system.
So, yes I suspect a leak. But until coolant level is verified we won’t know.
BTW, as a 2014 it is time for a drain and fill of the coolant (antifreeze) anyway.

Confirmed low coolant. Already have a service appointment this week, so we will add it to the list. Glad it is happening now while it is still under warranty!

I think you must have an extended warranty and if that is the case you need to read your contract to see if you are actually covered for this problem.

Get a jug of antifreeze compatible with the original Ford antifreeze. Buy 50/50 mix with water. Fill the cold radiator. Do this before you drive it again. If your next drive is to the dealer for the repair and it isn’t so far that the engine will overheat again, you probably don’t have to do this. Overheating can damage the engine severely, and the small cost of antifreeze pales in comparison to repairs or replacement of the engine.

Extended service warranty AND certified pre-owned. We’ll see.

At the risk of sounding super ignorant, is there a difference between putting the coolant in the coolant tank and in the radiator?

No one knows auto repairs without an education of some sort. Your ur question is not dumb.

Add coolant to the reservoir. The radiator is a pressurized system. If the engine is warm and you loosen the radiator cap, hot coolant will be pushed out by the pressure and you could be burned.

Wouldn’t it better to wait for the engine to cool and then carefully remove the radiator cap? Then fill the rad all the way and recap. Then see that the coolant reservoir level is between min and max level. If you only add coolant to the reservoir, you can’t be sure it will be drawn into the rest of the cooling system.


How was that confirmed? Did you wait for engine to cool completely and then open the radiator cap to see how much was there as well as how much is in reservoir?

If you were unable to refill the cooling system when you noticed the cooling system problem you should have had the vehicle towed to a repair shop. If you continue to drive the vehicle with a cooling system leak/low coolant until the engine fails the warranty company can deny the claim.

If they don’t find a leak, better check for a head gasket problem.

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I’m currently having the same exact issue except I noticed the coolant was low and topped it off. The following day my car had a similar experience where it was overheating then it wasn’t. Any tips or what did u do to fix the issue?

There are two basic types of modern cooling systems. The more common type has the coolant reservoir either on top or on one side of the radiator and it has a pressure relieving cap that keeps the cooling system under a given pressure when warm.

This system also has an overflow bottle where excess coolant goes when hot and it drawn back in to the radiator as it cools down. The overflow tank keeps the radiator completely full so there is no air circulating within the system. Air causes overheating.

If there is a breach in the caps gasket, or a leak in the hose that connects the radiator to the overflow tank, the coolant in the overflow can be at the correct level but the radiator can be low.

The other type uses an external coolant reservoir, no cap on the radiator or a sealed cap (not pressure limiting cap) and the external reservoir has a pressure relieving cap along with an air space to absorb the expansion and contraction.

In either case, when the coolant gets too low in the reservoir, air can be drawn into the cooling channels in the engine causing overheating. At a certain point, the coolant level is just low enough to pull in an air bubble, which pushes more coolant into the reservoir. The engine momentarily gets hotter as the coolant that was pushed into the reservoir now gets pulled into the engine to cool it down, The cycle keeps repeating.

This seems to happen more often with the external reservoirs. You only add coolant to the reservoir in the systems with the external reservoirs. In systems with overflow bottles, you must add coolant to the radiator first, then fill the overflow bottle to the cold line. If you only fill the overflow bottle, eventually the coolant will get drawn into the engine, but it can take several heat and cooling cycles for this, in the meantime, you engine is getting damaged.