Overheating warning issue after heater hose replacement

[kapdma]

I had the lower heater hose fail because the plastic Y broke while driving down the road. Temp gauge went red, overheating warning, and limp mode all kicked in and I pulled over and shut it off. After I replaced the hose and filled with coolant, I can't get the car to run right. When I turn the key on, the temp still shows it's overheating and the overheating warning comes on. Ignoring this, when I start it, it is in limp mode. This is when the car is cold, like hasn't been running for days. Any ideas?

 

[Hellwig]

I guess, this is caused by air bubbles.

 

[S20Workstation4]

It sounds like a computer issue. I would un-hook the battery overnight, to let the computer reset.

 

[JasonH]

I had the lower heater hose fail because the plastic Y broke while driving down the road. Temp gauge went red, overheating warning, and limp mode all kicked in and I pulled over and shut it off. After I replaced the hose and filled with coolant, I can't get the car to run right. When I turn the key on, the temp still shows it's overheating and the overheating warning comes on. Ignoring this, when I start it, it is in limp mode. This is when the car is cold, like hasn't been running for days. Any ideas?

As @Hellwig said, this is likely do to air in the cooling system. I found the below video from Ford Tech Makuloco helpful in purging mine after changing the water pump.

Ford Quick Tips #69: The Trick to Purging Air From Your Cooling System

Come along as we show you how to purge air from your engine cooling system.Vacuum Refill Tool-http://amzn.to/2iJT0GIVacuum Fill Tool Demonstration-https://ww...

www.youtube.com

 

[kapdma]

I've followed that video and done that many times. I also have it on an 8 degree incline according to the dashboard incline reading--the largest incline I can find in Florida. I can now get hot air after a minute or so, so I am getting coolant into the heater coil. But, it still goes nuts when the key is turned to "on". I'll try the battery disconnect thing.

 

[kapdma]

Just to close the loop, after disconnecting the battery and waiting 48 hours, the Ex still thinks it's overheating when cold and not even running. I cleared the overheating DTCs, and that fixed the issue. It no longer erroneously thinks it's overheating.