14 Temp Spike

[Joe Public]

I have no earthly idea how to search for this particular issue, so please forgive me if this has been talked about before.

I just recently bought a 2014 Expy EL 5.4l with approximately 90k miles on it. It’s in relatively good condition all things considered.

Issue: Yesterday I was sitting in a drive through on a rather hot day (NE FL inland). I noticed my radiator fans were at full speed, which I thought was regular considering the hot day. While waiting for food, I watched the temp gauge slowly climb - we got the food and started to drive, but then the temp gauge red lined and the display on the instrument panel showed the temp warning. No CEL at all.

I then got on the road and drove, thinking the car would cool down because air is now moving freely. The temp gauge went back down to normal (mid way) and it didn’t rise again through the rest of the hot day. I don’t remember if the fans were still on full blast as I didn’t realize this was going to be a reoccurring issue.

Today while driving into town, the temp gauge did the same thing - but this time it was a bit quicker in rising. The fans kicked on only a few minutes after driving (slow speed to get out of the neighborhood, then up to 65-70mph, back down to 35mph in the city). The temp gauge red lined, the warning popped up, but this time we had already reached our destination and the car was turned off.

We made another short trip and the temp gauge went from normal to rising while at idle. The fans were on again at full blast. I turned the car off, then back on when we left. While driving at highway speeds, the temp gauge went up again, but this time I turned the heat on (up to 80 on the driver side). The temp gauge normalized and was fine, but the heat was barely warm, not 80.

I haven’t checked the coolant level as I’m currently typing this in bed, but I will tomorrow when I get a chance.

When the temp goes up, the AC gets really cold. I haven’t noticed a performance difference in the vehicle. The temp gauge seems to red line, then go back down to normal and stay there for the remainder of the trip. No CEL yet.

An internet search with my limited knowledge/terminology only turns up F150 overheating issues. Any ideas or perhaps links to a previous post about this issue?

Thank you in advance!

 

[07navi]

I have no earthly idea how to search for this particular issue, so please forgive me if this has been talked about before.

I just recently bought a 2014 Expy EL 5.4l with approximately 90k miles on it. It’s in relatively good condition all things considered.

Issue: Yesterday I was sitting in a drive through on a rather hot day (NE FL inland). I noticed my radiator fans were at full speed, which I thought was regular considering the hot day. While waiting for food, I watched the temp gauge slowly climb - we got the food and started to drive, but then the temp gauge red lined and the display on the instrument panel showed the temp warning. No CEL at all.

I then got on the road and drove, thinking the car would cool down because air is now moving freely. The temp gauge went back down to normal (mid way) and it didn’t rise again through the rest of the hot day. I don’t remember if the fans were still on full blast as I didn’t realize this was going to be a reoccurring issue.

Today while driving into town, the temp gauge did the same thing - but this time it was a bit quicker in rising. The fans kicked on only a few minutes after driving (slow speed to get out of the neighborhood, then up to 65-70mph, back down to 35mph in the city). The temp gauge red lined, the warning popped up, but this time we had already reached our destination and the car was turned off.

We made another short trip and the temp gauge went from normal to rising while at idle. The fans were on again at full blast. I turned the car off, then back on when we left. While driving at highway speeds, the temp gauge went up again, but this time I turned the heat on (up to 80 on the driver side). The temp gauge normalized and was fine, but the heat was barely warm, not 80.

I haven’t checked the coolant level as I’m currently typing this in bed, but I will tomorrow when I get a chance.

When the temp goes up, the AC gets really cold. I haven’t noticed a performance difference in the vehicle. The temp gauge seems to red line, then go back down to normal and stay there for the remainder of the trip. No CEL yet.

An internet search with my limited knowledge/terminology only turns up F150 overheating issues. Any ideas or perhaps links to a previous post about this issue?

Thank you in advance!

It isn't getting that hot because it didn't go into limp mode plus when the outside temp goes up the AC gets warmer too, not colder. Drain a little water out of the rad and see how hot it is.

 

[Joe Public]

Thanks for the response! I’ll look into that once I can check coolant levels.

Let me say this: perhaps there’s no correlation between the engine temp spiking and the AC getting colder - this all happened today after a cold start on a hot day; the AC could’ve just gotten down to normal when I noticed the fans going nuts.

 

[07navi]

Thanks for the response! I’ll look into that once I can check coolant levels.

Let me say this: perhaps there’s no correlation between the engine temp spiking and the AC getting colder - this all happened today after a cold start on a hot day; the AC could’ve just gotten down to normal when I noticed the fans going nuts.

The fans do pull more air across the condenser when they speed up but it doesn't take much airflow to cool the ac down. Maybe your fans are getting false signals. When you think the engine is really hot drain a quart of water and put a thermometer in it or just feel the sides of the container or run your hand across the stream. It might just seem like it's getting hot. Check the OBD II with a scanner for codes also.

 

[Boostedbus]

As long as the coolant level is correct, I’d suspect sticking thermostat. The T-stat can be sticking closed and making the engine hot and the radiator cold which in turn would make the A/C colder because the radiator isn’t heating up the condenser.

 

[Joe Public]

As long as the coolant level is correct, I’d suspect sticking thermostat. The T-stat can be sticking closed and making the engine hot and the radiator cold which in turn would make the A/C colder because the radiator isn’t heating up the condenser.

The coolant level was low. I filled it up to the line; we’ll see what happens if the wife drives it today.

Thanks again for everyone’s replies!

 

[Boostedbus]

The coolant level was low. I filled it up to the line; we’ll see what happens if the wife drives it today.

Thanks again for everyone’s replies!

How low?

 

[ExplorerTom]

I’ve noticed the same with mine. I changed out my thermostat and flushed the radiator too. Still does it- although mine doesn’t do it as bad as yours. My 2014 will get up to 220 while idling for an extended period of time (drive thru or whatever) but cools back down to 190 once I get moving. The factory needle doesn’t register any movement during this. I read it through an UltraGauge.

 

[Joe Public]

How low?

It was 3AM when I checked using the light on my phone, but I’d say it was low enough to not see it through the side of the reservoir. I could only see the fluid in it when I opened the top.

I’ve noticed the same with mine. I changed out my thermostat and flushed the radiator too. Still does it- although mine doesn’t do it as bad as yours. My 2014 will get up to 220 while idling for an extended period of time (drive thru or whatever) but cools back down to 190 once I get moving. The factory needle doesn’t register any movement during this. I read it through an UltraGauge.

I’m certainly hoping a new thermostat will help if the problem persists now.

No new update as of now. I will update if/when the vehicle gets driven.

Thanks again, everyone!

 

[Don Hall]

Cooling is a simple equation. All that is needed is coolant flow, and air flow.
Stop one, or both, and you will experience overheating.

Your truck uses a closed cooling system. As the coolant heats, it expands, and
travels to the overflow bottle. When it cools, it reverses flow via a siphon back to the radiator. Outside air does not enter the 'closed' system. If it does, no siphon will occur, and the coolant level will keep getting lower.

How air enters the cooling system.....deformed cap gasket, loose/damaged connections, any unit failure/break in the system.

As mentioned, a properly working t-stat is important. A t-stat that only opens
partially, or not at all, will cause overheating. To check a t-stat, remove it, and
place it in boiling water to determine if it opens, or not.

Of course, the coolant must always be at the 'full' level. If continued filling is required, you need to check for leaks. A simple pressure test using a pump connected to the rad cap opening will detect any leaks. To check the block, the
t-stat must be removed.

Ensure the fans activate at the proper temps, check a maintenance manual for fan activation temps (I didn't see any temp numbers in my Owners Manual).

 

[07navi]

You can borrow a pressure tester a O'reilys for the cap but I would just throw a new cap and stat in there for starters.

 

[Joe Public]

Cooling is a simple equation. All that is needed is coolant flow, and air flow.
Stop one, or both, and you will experience overheating.

Your truck uses a closed cooling system. As the coolant heats, it expands, and
travels to the overflow bottle. When it cools, it reverses flow via a siphon back to the radiator. Outside air does not enter the 'closed' system. If it does, no siphon will occur, and the coolant level will keep getting lower.

How air enters the cooling system.....deformed cap gasket, loose/damaged connections, any unit failure/break in the system.

As mentioned, a properly working t-stat is important. A t-stat that only opens
partially, or not at all, will cause overheating. To check a t-stat, remove it, and
place it in boiling water to determine if it opens, or not.

Of course, the coolant must always be at the 'full' level. If continued filling is required, you need to check for leaks. A simple pressure test using a pump connected to the rad cap opening will detect any leaks. To check the block, the
t-stat must be removed.

Ensure the fans activate at the proper temps, check a maintenance manual for fan activation temps (I didn't see any temp numbers in my Owners Manual).

Thank you for your explanation! That makes a lot of sense. Your response has been noted!

Update: After replacing the thermostat (Advanced Auto “premium” brand; no Ford OEM in stock - was looking for a quick fix) and driving the truck around the block, I was sitting in it typing this response. The temp gauge was dang-near on red, so I figured I’d shut it off. Once off, I noticed white fumes coming from the hood.

Attached is my best attempt at showing where the vaporized coolant is coming from - I believe it could be coming from the “gasket” between the hose/stat combo piece and the engine (if that even makes sense). In the first pic you can see a plastic or rubber nub sticking through the metal piece towards the upper left hand corner - that’s part of the “gasket” I’m talking about. Can this be a point of failure?

Clearly this isn’t normal. I also have zero heat in the cab, even when the AC is at 90 and the AC fans are on full blast. After the ride around the block and sitting in the truck for a minute, I was starting to get brief hints of warm air, but it quickly returned to cold/cool air.

Does this information help? My dad tossed in the idea of the water pump being bad, but I neglected to even look at it before coming in for the night.

 

[Don Hall]

Nice explanation, and photos, Joe. My '04 only has 19K miles on it, so I am not familiar with the engine compartment. I don't recognize a t-stat housing in the photos. I see the 'bulge' you reference, but I can't tell you what it is.

From your explanation: "driving the truck around the block, I was sitting in it typing this response. The temp gauge was dang-near on red". It would seem that the water pump could be your problem. Overheating in such a short drive indicates a lack of coolant flow. Fumes coming from the engine bay confirm that the temp gage is not the culprit.

The following is a link to diagnose a faulty water pump: https://www.yourmechanic.com/article/how-to-diagnose-a-faulty-water-pump-by-rocco-lovetere#:~:text=There are several safe ways to inspect if,for leaks. Step 6: Inspect the coolant reservoir.

 

[07navi]

That is just the shape of the gasket. Thermostats are critical on these modular engines, there is a top and bottom valve and they have to function well. The bottom part closes off another passage and needs to function right. I highly recommend you take it out and put a Motorcraft one in. I will see if I can find some diagrams on that.

 

[ExplorerTom]

I’d say either water pump and/or air in the system.

 

[JExpedition07]

Have you verified both fans are operating and not just one?

 

[Joe Public]

Nice explanation, and photos, Joe. My '04 only has 19K miles on it, so I am not familiar with the engine compartment. I don't recognize a t-stat housing in the photos. I see the 'bulge' you reference, but I can't tell you what it is.

From your explanation: "driving the truck around the block, I was sitting in it typing this response. The temp gauge was dang-near on red". It would seem that the water pump could be your problem. Overheating in such a short drive indicates a lack of coolant flow. Fumes coming from the engine bay confirm that the temp gage is not the culprit.

The following is a link to diagnose a faulty water pump: https://www.yourmechanic.com/article/how-to-diagnose-a-faulty-water-pump-by-rocco-lovetere#:~:text=There are several safe ways to inspect if,for leaks. Step 6: Inspect the coolant reservoir.

Thank you! I’ll read that soon. I wonder if replacing the water pump is something I can do in my own driveway.

That is just the shape of the gasket. Thermostats are critical on these modular engines, there is a top and bottom valve and they have to function well. The bottom part closes off another passage and needs to function right. I highly recommend you take it out and put a Motorcraft one in. I will see if I can find some diagrams on that.

Please excuse my explanation or description, I was using that nub as a reference point for the particular “gasket.” It looks like the steam or vapor was coming from that location.

As for the Ford OEM thermostat, I figured as much. I will try to get my hands on one and hopefully I can return the “premium” brand thermostat.

Thank you all again for your help! I’d be stoked if I can fix this myself!

 

[Joe Public]

I’d say either water pump and/or air in the system.

I saw that exact video not too long ago; that idea crossed my mind. I’ll certainly try whatever I can to not spend money.

Have you verified both fans are operating and not just one?

Good question - in fact, I have not. I just assumed the jet engine noise meant both were functioning. I’ll check on that, as well.

 

[07navi]

Thank you! I’ll read that soon. I wonder if replacing the water pump is something I can do in my own driveway.




Please excuse my explanation or description, I was using that nub as a reference point for the particular “gasket.” It looks like the steam or vapor was coming from that location.

As for the Ford OEM thermostat, I figured as much. I will try to get my hands on one and hopefully I can return the “premium” brand thermostat.

Thank you all again for your help! I’d be stoked if I can fix this myself!

That bottom passage has to work right or it will heat up, many aftermarket thermostats won't close it off right or at all.

 

[Joe Public]

Alright, update!

Today I replaced the thermostat (OEM), the water pump (OEM), the serpentine belt (I can’t remember the brand), and the radiator cap (Stant). In refilling the radiator, I burped the system, as well.
One or all of these, minus the belt, seems to have fixed the overheating/temp spike and restored heat in the cab. I still need to go out for an extended drive to make sure everything is good.

I might have a coolant leak, however. I’m not sure how much coolant is still hanging around in some nook or cranny underneath the car, but I can say there was a puddle underneath the car collecting/dripping from the transmission/close to the oil pan.

I also might have not refilled the system enough, therefore the plastic reservoir is depleting overtime - so this coupled with the old coolant under the truck could give the impression of a leak.

I have two more gallons of orange coolant that I’ll keep around for refilling the system.

Question: is adding extra coolant from the plastic reservoir ok? Or should I pull the radiator cap and fill from there?

Thank you EVERYONE for all of your recommendations, advice, and replies!