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2016 fiesta st overheating

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Location
Austin
Sorry man, it mentiona radiator upgrades under street touring. And nobody would dispute the thermostat because its allowed... but if it werent you are right.. it would be hard to prove. I hear the weight of guilt slows you down on course though.. ??????
 


alexrex20

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I did some informal testing yesterday. Ambient temperature was 98F. In City driving my water temp was up to 235, especially while sitting at a red light. My AC was on and according to the Accessport, the fans were at 92%. I then tried with AC off and because it took me awhile to figure out how to use the video function on my dang phone, there was a few minutes of AC off and believe it or not the coolant temp dropped to 205 and stayed there. As soon as I turned the AC back on the coolant temp immediately started to pick up again. I drove a few more miles and it stabilized around 220, so I tried one more time and turned the AC off. Sure enough the temperature slowly dropped down to about 207. When I turn to the AC back on, temps slowly climbed to about 220 again and again they stayed there.

I will have to get this on video next time, and perhaps maybe have a more consistent test procedure not affected by traffic lights. I will probably try to my driveway, and I can also test to see how quickly coolant temp will drop when I turn on the heater.

Frankly, I'm not surprised that coolant temps shoot up when I turn the AC on. The cooling system is already taxed more by my larger intercooler. And with the AC on, the air is heated even more going through the condenser, before it goes through the radiator.

On a side note I did get it up to 4 bars on the gauge. I quickly grabbed my accessport and plugged it in but by the time it loaded it was down to three bars and temp was 232. It's weird because later on while I was monitoring the temp did go back up to 235 but it stayed at two bars. It's very inconsistent what each bar means.

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Intuit

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YES, this!^^^

IF it is running on max speed most of the time, I'm guessing that would shorten it's life, no?
Seriously doubt that there would be any problems with durability in a modern electric fan. Electric motors are extremely reliable, with exception to power windows because they're routinely undersized (read: cheap) for the task.


245 F for limp mode. 189 F for thermostat starting to open, 207 F for full open. .........
Great info.

I did some informal testing yesterday. Ambient temperature was 98F. In City driving my water temp was up to 235, especially while sitting at a red light. My AC was on and according to the Accessport, the fans were at 92%. I then tried with AC off and because it took me awhile to figure out how to use the video function on my dang phone, there was a few minutes of AC off and believe it or not the coolant temp dropped to 205 and stayed there. As soon as I turned the AC back on the coolant temp immediately started to pick up again. I drove a few more miles and it stabilized around 220, so I tried one more time and turned the AC off. Sure enough the temperature slowly dropped down to about 207. When I turn to the AC back on, temps slowly climbed to about 220 again and again they stayed there.

I will have to get this on video next time, and perhaps maybe have a more consistent test procedure not affected by traffic lights. I will probably try to my driveway, and I can also test to see how quickly coolant temp will drop when I turn on the heater.

Frankly, I'm not surprised that coolant temps shoot up when I turn the AC on. The cooling system is already taxed more by my larger intercooler. And with the AC on, the air is heated even more going through the condenser, before it goes through the radiator.

On a side note I did get it up to 4 bars on the gauge. I quickly grabbed my accessport and plugged it in but by the time it loaded it was down to three bars and temp was 232. It's weird because later on while I was monitoring the temp did go back up to 235 but it stayed at two bars. It's very inconsistent what each bar means.

Sent from my SM-G950U using Tapatalk
Not only is all the heat in the cabin being cycled into the engine, but the engine has to work significantly harder to run the compressor. A prior vehicle had an A/C compressor relay fail. In anticipation of the missing load, the engine RPM would double the normal idle RPM. Of course, when the relay worked and the compressor engaged, RPMs stayed normal.
 


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Location
Plensdorf
So...to those who believe it's a fluke and statistically improbable....my 2016 FiST is in the shop for...wait....OVERHEATING... completely stock. But that's not all. This is my SECOND FiST with an overheating problem. I've written alot here about my 2014 FiST that started overheating @20k then the dealer could never diagnose only to find 3K after the drivetrain warranty expired that I had the dreaded cylinder 3 coolant issue. Engine was replaced only to have it too start overheating. Sold car at a major loss and purchased my current 2016. This one now started overheating at around 18k and now sits at the shop after limp mode three times in ambient temps of 95, 90 and 87 degrees. I will keep y'all posted on the outcome but this has no gotten to where I am unable to drive in ambient temps over 85 in traffic. I have been able to grab some data with Forscan that shows the intake air temp spikes to 150 degrees which overwhelms the cooling system. Coolant spikes to 245+.
 


M-Sport fan

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I am going to have to drive around with my kiwi wifi OBD2/OLDER iPod with the Dash Command app constantly hooked up and on to coolant temp (I own an AP, but I will not leave it IN the car, hooked up, as some do, since this is WAY TOO tempting), since I have a Skid Plate Guy plate on it's way to me, and unless someone knows. or can tell me otherwise, I cannot see how that can help this issue. [dunno]

I sense a Mountune radiator in my near future.
 


alexrex20

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I wish Ron carried the mountune radiator and not just the mishimoto. Any other good vendors I should get the mountune from instead of ordering direct?

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jmrtsus

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I wish Ron carried the mountune radiator and not just the mishimoto. Any other good vendors I should get the mountune from instead of ordering direct?

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Try Ford Performance dealers like Levittown Ford. I got my MP-215 at a $200 discount from them a couple of years ago. My 16 has never seen anything over "normal" with the MP-215 no matter what the ambient temp or hard driving. I have yet to hear of MP-215 cars overheating on hard driving.
 


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Location
Austin
I am going to have to drive around with my kiwi wifi OBD2/OLDER iPod with the Dash Command app constantly hooked up and on to coolant temp (I own an AP, but I will not leave it IN the car, hooked up, as some do, since this is WAY TOO tempting), since I have a Skid Plate Guy plate on it's way to me, and unless someone knows. or can tell me otherwise, I cannot see how that can help this issue. [dunno]

I sense a Mountune radiator in my near future.
The skid plate might help with cooling, less pressure behind the radiator means more air through it
 


alexrex20

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Try Ford Performance dealers like Levittown Ford. I got my MP-215 at a $200 discount from them a couple of years ago. My 16 has never seen anything over "normal" with the MP-215 no matter what the ambient temp or hard driving. I have yet to hear of MP-215 cars overheating on hard driving.
What ambient temp do y'all get in the summer?

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jmrtsus

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What ambient temp do y'all get in the summer?

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We get high 90's and over 100 sometimes. I have been in hours of stop and go traffic with A/C on full blast. I have traveled extensively in the plains and deserts in the summer. I have run the Tail of the Dragon several times in the summer heat. Again I have never seen anything but normal temps. Most over heating issues are from mods. I understand that but unlike others I don't see that as a Ford issue. I think we have the usual bad parts covered under warranty. So as advertised my car with the MP-215 is trouble free. I would love to see a poll of just what tunes work with the stock cooling and which do not. In other words does a Cobb for example, stage 1 tune and no other mods have overheating issues? What mods like bigger IC or oil cooler increase temps? As it stands all we know for sure is the more mods the higher the temps. Nothing new or Mountune would not offer a radiator upgrade. So at what point do you really need to upgrade. My car and driving conditions show no indications of needing upgrading.
 


alexrex20

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I think a large part of the overheating issues is having a larger intercooler. The more heat the intercooler extracts from the charge air, the more heat goes directly into the radiator. I never noticed any overheating or even higher-than-normal coolant temps before I upgraded my intercooler.

If one is not having any overheating issues, then I agree, there is no reason to upgrade the radiator. But I wouldn't go so far as to say that overheating is caused by certain Tunes or mods. There are many people that have overheating problems with bone stock cars.

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M-Sport fan

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The skid plate might help with cooling, less pressure behind the radiator means more air through it
OK, THANKS, since this is the type of info I was looking for! [thumb]

Anyone on here with one of these skid plates installed with any (tested) definitive/empirical data on whether this is the actual case in practice or not? [dunno]
 


alexrex20

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Skid plates often improve cooling efficiency and fuel economy, specifically on lifted trucks/SUVs. Air is a wonderful thing, although usually it works against you.

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alexrex20

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OK, THANKS, since this is the type of info I was looking for! [thumb]

Anyone on here with one of these skid plates installed with any (tested) definitive/empirical data on whether this is the actual case in practice or not? [dunno]
just gave ya your 1000th like ;)
 


Messages
62
Likes
19
Location
Plensdorf
UPDATE
The verdict is in and my 2016 FiST has a coolant leak in cylinder 3. Exactly what has happened on two other engines. Ford continues to believe that the engine/gasket/head is the cause and just continues to replace them. They continue to address only the symptom and never address the root cause. This car is experiencing exactly the fate of my 2014 and bears the same exact parts but is NOT included in the 1.6t recall. I love this car dearly but cannot fathom the thought of dealing with the debacle again. I'm awaiting the decision on engine/head replacement.
 


M-Sport fan

9000 Post Club
Messages
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6,697
Location
Princeton, N.J.
UPDATE
The verdict is in and my 2016 FiST has a coolant leak in cylinder 3. Exactly what has happened on two other engines. Ford continues to believe that the engine/gasket/head is the cause and just continues to replace them. They continue to address only the symptom and never address the root cause. This car is experiencing exactly the fate of my 2014 and bears the same exact parts but is NOT included in the 1.6t recall. I love this car dearly but cannot fathom the thought of dealing with the debacle again. I'm awaiting the decision on engine/head replacement.
At this point, they should just go ahead and buy you, and install for you, a Mountune radiator, as it will save THEM all of that engine/head replacement coin in the future. ;)
 


Messages
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Location
Plensdorf
Oh I agree. Even suggested that last time but was told that it would most certainly void any warranty claims in the future.
 




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