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Overheated

Messages
334
Likes
54
Location
Port Hueneme
#1
Ok so this was some negligence on my part because I knew my coolant level was at minimum or maybe even slightly below but my car overheated for the first time on my way home from work and coolant levels reached 245 degrees on my AP. I couldn't pull over right away but as soon as I could the coolant temps were 230 degrees. I let the car cool down for about an hour and topped if off with coolant at the gas station. My question is because it scared me driving like that for about 2-3 mins until I got off the freeway did I do any serious or potential damage to the engine?
 


VirtualRonin

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Active Military
Messages
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452
Location
Spring Lake Park, MN
#2
Ok so this was some negligence on my part because I knew my coolant level was at minimum or maybe even slightly below but my car overheated for the first time on my way home from work and coolant levels reached 245 degrees on my AP. I couldn't pull over right away but as soon as I could the coolant temps were 230 degrees. I let the car cool down for about an hour and topped if off with coolant at the gas station. My question is because it scared me driving like that for about 2-3 mins until I got off the freeway did I do any serious or potential damage to the engine?
That happened to me last summer here in Texas. My car went into limp mode and I pulled off the highway and let it cool down. No issues thankfully. After that happened, anytime I would get near the overheat temp I would roll down my windows and turn up the heater and fan to max heat to aid bringing down temps. I suggest you do that if you get up to 240 degrees or higher. Since then I've upgraded my radiator and I stay under 200 degrees on my coolant temps.

You should be ok, just monitor your coolant level.


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Messages
203
Likes
42
Location
Dallas
#3
That happened to me last summer here in Texas. My car went into limp mode and I pulled off the highway and let it cool down. No issues thankfully. After that happened, anytime I would get near the overheat temp I would roll down my windows and turn up the heater and fan to max heat to aid bringing down temps. I suggest you do that if you get up to 240 degrees or higher. Since then I've upgraded my radiator and I stay under 200 degrees on my coolant temps.

You should be ok, just monitor your coolant level.


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***THIS***

Happened to me 3-4 times in TX heat last summer as well?!? Dealer finally found a code that was thrown, changed a module...car did it again 3 days later?!? I have a Mishimoto radiator sitting in the garage to be installed here pretty quick.

We shall see...
 


VirtualRonin

Active member
Active Military
Messages
557
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452
Location
Spring Lake Park, MN
#4
***THIS***

Happened to me 3-4 times in TX heat last summer as well?!? Dealer finally found a code that was thrown, changed a module...car did it again 3 days later?!? I have a Mishimoto radiator sitting in the garage to be installed here pretty quick.

We shall see...
The Mishi radiator will not disappoint! I'm still running Ford 50/50 coolant as well and my coolant temps run around 192-194 when up to temp and never goes over. Oil temps run about the same temp as well on my AP. It's a huge improvement over stock and the best money I've spent because now I don't have any worries daily driving in 100+ degree weather in traffic, hills, etc.


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Messages
203
Likes
42
Location
Dallas
#5
The Mishi radiator will not disappoint! I'm still running Ford 50/50 coolant as well and my coolant temps run around 192-194 when up to temp and never goes over. Oil temps run about the same temp as well on my AP. It's a huge improvement over stock and the best money I've spent because now I don't have any worries daily driving in 100+ degree weather in traffic, hills, etc.


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This is GREAT news! I bought this thing in the middle of summer last year and just never got around to installing. Did you have someone do it or DIY? I'm trying to determine what a shop would charge to do it as I just don't have time right now to mess with it.
 


VirtualRonin

Active member
Active Military
Messages
557
Likes
452
Location
Spring Lake Park, MN
#6
This is GREAT news! I bought this thing in the middle of summer last year and just never got around to installing. Did you have someone do it or DIY? I'm trying to determine what a shop would charge to do it as I just don't have time right now to mess with it.
I did it myself at the auto hobby shop on base but I think it can easily be done in a garage. Just need a couple jack stands to hold the crash beam up off the ground once you unbolt it. I think I had it all done start to finish in about 6 hours, and I was taking my time. Plus it was just me so if you get a buddy to help it should speed it up a bit. You won't lose too much coolant when you drain the tiny stock radiator, maybe a gallon all together but get 2 gallons just in case. The instructions from Mishimoto are pretty complete if I remember correctly.


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OP
D
Messages
334
Likes
54
Location
Port Hueneme
Thread Starter #7
That happened to me last summer here in Texas. My car went into limp mode and I pulled off the highway and let it cool down. No issues thankfully. After that happened, anytime I would get near the overheat temp I would roll down my windows and turn up the heater and fan to max heat to aid bringing down temps. I suggest you do that if you get up to 240 degrees or higher. Since then I've upgraded my radiator and I stay under 200 degrees on my coolant temps.

You should be ok, just monitor your coolant level.


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I have a mishimoto radiator and thermostat too waiting to be installed on the car. I still got nervous and hoping it didn't cause any worse issues.
 


Messages
203
Likes
42
Location
Dallas
#8
I have a mishimoto radiator and thermostat too waiting to be installed on the car. I still got nervous and hoping it didn't cause any worse issues.
I think you are OK. Like I said, I had it happen to me 4-5x in 105 degree TX heat last summer and there were no ill effects.
 


OP
D
Messages
334
Likes
54
Location
Port Hueneme
Thread Starter #9
Thanks guys! I can't wait to install my parts. Hopefully that never happens again.
 


Messages
216
Likes
46
Location
Texas
#10
When I have had a similar issue, also in Texas, but not on my FiST; it was a failing thermostat that wasnt letting the coolant loose to run around and do its thing. Got to that result after pressure testing the cooling system for leaks.

Green Beast/TShirt Driving/Pete has an install video of the Mishi Thermostat on his youtube. Looks like a beast of an install based on what you have to pull off to get to the thermostat, but he has lots of good info on the video.

Edit to add Video

https://www.youtube.com/watch?v=Z9G2_1soVDE&t=346s
 


OP
D
Messages
334
Likes
54
Location
Port Hueneme
Thread Starter #11
When I have had a similar issue, also in Texas, but not on my FiST; it was a failing thermostat that wasnt letting the coolant loose to run around and do its thing. Got to that result after pressure testing the cooling system for leaks.

Green Beast/TShirt Driving/Pete has an install video of the Mishi Thermostat on his youtube. Looks like a beast of an install based on what you have to pull off to get to the thermostat, but he has lots of good info on the video.

Edit to add Video

https://www.youtube.com/watch?v=Z9G2_1soVDE&t=346s
Ford engineers really fucked up on that design on the thermostat. I've seen petes video and have been dreading this install but after that incident yesterday it's gonna motivate me to install this sooner then later.
 


Messages
49
Likes
24
Location
Oakley
#12
It is safe to assume that the issue is a failing thermostat or are y'all saying that the stock cooling system has a design flaw and will allow the car to overheat even when all parts are in spec??


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OP
D
Messages
334
Likes
54
Location
Port Hueneme
Thread Starter #13
It is safe to assume that the issue is a failing thermostat or are y'all saying that the stock cooling system has a design flaw and will allow the car to overheat even when all parts are in spec??


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For me I think the coolant level was too low and air got into the system causing that temp spike. I've never had any issues till now. But I'm still changing out all the stock cooling parts
 


Messages
203
Likes
42
Location
Dallas
#14
It is safe to assume that the issue is a failing thermostat or are y'all saying that the stock cooling system has a design flaw and will allow the car to overheat even when all parts are in spec??


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Many, many, many threads on this issue. I don't think "anyone" has a clear answer as to "why" it happens?!? The only solution I've seen has been Mishimoto Radiator and thermostat. I'm going to break down and install mine that has been gathering dust for since summer.

I think I read somewhere that another company was manufacturing radiators now?!?
 


Messages
231
Likes
135
Location
Corsicana
#15
This is GREAT news! I bought this thing in the middle of summer last year and just never got around to installing. Did you have someone do it or DIY? I'm trying to determine what a shop would charge to do it as I just don't have time right now to mess with it.
The install isn't too bad, just tedious. I soloed it with basic hand tools in like 4 hours. If you need help, I only live about 40 minutes south of Dallas. It wouldn't take long to install. It's soooooo worth it in a hot climate like ours. Before, I'd ping 245 degrees just driving around town at low speeds or sitting in traffic. Now I sit at 190-195 no matter what I'm doing. Definitely a must-have mod on the FiST if you live in a hot climate like ours.
 


Messages
231
Likes
135
Location
Corsicana
#17
For me I think the coolant level was too low and air got into the system causing that temp spike. I've never had any issues till now. But I'm still changing out all the stock cooling parts
Just my opinion, but I wouldn't bother going through all the extra trouble of replacing the thermostat. I'm a hybrid turbo (X-47) like you, and the Mishi radiator works just fine. I stay below 200 degrees, even when I'm pushing the car hard.
 


OP
D
Messages
334
Likes
54
Location
Port Hueneme
Thread Starter #18
Just my opinion, but I wouldn't bother going through all the extra trouble of replacing the thermostat. I'm a hybrid turbo (X-47) like you, and the Mishi radiator works just fine. I stay below 200 degrees, even when I'm pushing the car hard.
I'm planning on going with the 360r kit in the near future so I think it will be a good insurance for the car. My mechanic will have the fun of installing it while I'm on vacation in Colorado :)
 


VirtualRonin

Active member
Active Military
Messages
557
Likes
452
Location
Spring Lake Park, MN
#19
It is safe to assume that the issue is a failing thermostat or are y'all saying that the stock cooling system has a design flaw and will allow the car to overheat even when all parts are in spec??


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IMO, the stock cooling system is adequate for most driving situations as long as you keep the stock intercooler in place. I ran mine when it was mostly stock in a local PDX (Performance Driving Experience). It was about an 80 degree day, sunny. The track was short, maybe 1-1.5 miles in length. I ran four 20 min sessions and only got into high temp range on my last run. I got the temp dummy light and did a cool down run. Temp light went away and I finished out the day.

I believe the cooling issues are more prone to happen after upgrading to a bar and plate intercooler, which is great for charge temps but blocks more air trying to get to the bottom portion of the radiator. When ambient temps are 90+ and your driving hard you start hitting those high temps much sooner. Thats likely why the Mountune intercooler is tube and fin; it is meant to work with the stock cooling system without compromising it but it's not as efficient as the bar and plate at dropping charge temps.

That being said, the stock radiator is laughably small. I didn't fully appreciate that until I removed it. I have not changed my thermostat; the radiator upgrade fixed the cooling issue to my satisfaction.

I moved to TX from MN last July and after driving my car in traffic in 100+ degree weather my cooling system couldn't keep up and it was necessary to address the cooling issue. It's no fun driving in that heat with the windows down and the heater on full blast just to keep from overheating [emoji29]


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Messages
159
Likes
59
Location
Wichita
#20
I remember asking the octane academy instructors. Aside from the extra hydraulic brakes, the fiestas were stock. However, they did modify the focus due to cooling problems. They run those cars pretty hard in the summer heat. So it would seem to be related to aftermarket changes.

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