Overheating message

[dlcorbett]

Has anyone seen an "overheating coolant" message for their 2015+ expys? What did your dealer or mechanic say about this?Got the message though the temp gauge showed Cold, and now the truck is undrivable.

 

[JExpedition07]

Does the truck turn over and start? When did this occur? What confuses me is you said it’s not driveable. I’m not sure on the 3.5 EcoBoost but on the 5.4 Triton there is a fail safe cooling mode in the event of a failure. The ECM alternates cylinders and shuts off combustion to pump air through the engine to cool. You get a warning but the engine won’t shut down for safety reasons.

I guess it’s possible that’s not smart on the ecoboost with the extra heat of the turbos...was the engine cool and recently started? Maybe a sensor mishap? You sure have had no breaks with this truck, she has been a shop queen. Hope all gets sorted out.

Since I’m not an ecoboost owner nor have I had an overheat I’m no help. Hopefully others chime in and my reply acts as a “bump” for you.

 

[1955moose]

As usual, the $64.00 question is are you doing the work? Or a shop? If your doing the work, obviously you start at the basics. Does it have sufficient coolant, is the thermostat opening at desired temp, is fan switch kicking fan on. Beyond that, it gets fun. Is the radiator flowing, is the pump pumping? Etc, etc.

Sent from my N9131 using Tapatalk

 

[dlcorbett]

Honestly, its not mine. A friends truck juat started doing this by her knowledge today and almost left her stranded.

 

[1955moose]

Well we can turn this into a 25 plus post hypothesis, or she can bring it to the dealer/shop, and report back what it took to fix. We live to help here, but if she's having it repaired, rather than doing it herself, it would save a ton of time, and effort on all concerned. Thanks for being honest on whose vehicle it is.

Sent from my N9131 using Tapatalk

 

[Pilgrim]

What was the end of this? I had the same issue but hooked up a scanner and watched temps. All over and very erratic. Goes from 195 down to 25 degrees in about 1 second. Never shows overheating, but does trigger the "coolant overheating" message on the message center. It does not seem like it's overheating under the hood. It acts like a faulty sender, except it never goes over 195 and I can't explain the overheating message on the message center.

 

[07navi]

Like it said above it should go into limp where it fires on 4 cylinders, alternates firing pattern, induces cool air, drops your max speed down to about 50, and eventually will shut down but will restart and go through the same pattern to get you to a safe place. Maybe the Ecoboost doesn't have that feature IDK. Just being low on water will induce limp mode. A big mistake people make is putting an aftermarket thermostat in these modulars which doesn't shut off and regulate the bottom passage correctly. It's definitely best to spend a couple more dollars and get the proper Motorcraft thermostat. It's not like 30 years ago when thermostats just open and close at the right time. Also being very low on water can lose water/coolant contact with the sender giving erratic and inaccurate readings.

 

[ManUpOrShutUp]

Like it said above it should go into limp where it fires on 4 cylinders, alternates firing pattern, induces cool air, and eventually will shut down but will restart and go through the same pattern to get you to a safe place. Maybe the Ecoboost doesn't have that feature IDK. Just being low on water will induce limp mode. A big mistake people make is putting an aftermarket thermostat in these modulars which doesn't shut off and regulate the bottom passage correctly. It's definitely best to spend a couple more dollars and get the proper Motorcraft thermostat. It's not like 30 years ago when thermostats just open and close at the right time. Also being very low on water can lose water/coolant contact with the sender giving erratic and inaccurate readings.

My OEM tstat crapped out 4 years in. Originally, I picked up a Motorcraft replacement from the dealership, but it weighed about 1/2 of the OEM one and just seemed like it was poorly constructed. I ended up going with a Stant Superstat (OEM temp) and it's been great. Temps are very steady and it's coming up on 5 years since I installed it.

 

[07navi]

My OEM tstat crapped out 4 years in. Originally, I picked up a Motorcraft replacement from the dealership, but it weighed about 1/2 of the OEM one and just seemed like it was poorly constructed. I ended up going with a Stant Superstat (OEM temp) and it's been great. Temps are very steady and it's coming up on 5 years since I installed it.

And the point?

Not saying all aftermarket ones are bad but they need to be made correctly for these engines. My Motorcraft one was fine the whole 12 years I had my last truck.

 

[762mm]

Under these conditions, I'd do the following fairly cheap solutions, in this order and see if it helps :

1. Check proper coolant level.

2. Change thermostat.

3. Flush heater core.

4. Replace temp sensor, or at least make sure electrical connection is clean on it. Check connector and wiring.

4. Remove and inspect water pump. The Ecoboost have plastic fins in their WP, I believe. Those are known to break off sometimes, thus you could get no coolant circulation.

5. Inspect truck's computer to see if it's not gone bad, thus generating false readings.