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2016 fiesta st overheating

Truth in Ruin

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Has anybody ever verified coolant temps to the diaplayed temp on the Accessport? I know on fully cold starts my AP is already reading coolant temps about 15deg hotter than it should. For example this morning it was 85F and as soon as I started it up and the AP loaded, it was reading 103F. There's no way my coolant wasn't at ambient. There's also no way it warmed up 18deg in 5 seconds.

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That's normal. Steel absorbs heat, especially if it's getting sunlight.
 


Truth in Ruin

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The heat from sitting under the oak tree overnight?

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I work for a major transportation company; part of my job to check metal temperatures. The metal is always warmer than ambient temps. I've seen 136* on 95* days, so 18* doesn't surprise me.
 


alexrex20

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I'm not buying it. There is no sunlight or source of heat as my car sits in the driveway overnight. It's not retaining 15deg of heat.

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Truth in Ruin

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Think of it this way: as soon as you turn off your engine--the temperatures rise higher, and higher. The metal your engine is built out of holds in the heat as does the concrete your car is parked on. The fenders and hood create a bowl effect trapping in the heat. Heat rises with nowhere to go. The air you live in cools faster than the metal under your hood.

Documenting metal temps is apart of what I do for a living, and the metal temperatures I check are ALWAYS warmer than the air.

I'm not trying to be demeaning, or anything like that, I'm just telling you what I've experienced.
 


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Had a total meltdown yesterday, even had the over heat alarm go off. I went for a day trip for about 700km drive. In the morning it was colder 14C. Normally where I first had the car overheat in 29C since it was cold that day I saw the bar go up once and I was going about 120-40KM/h following the traffic up the Coquihalla Hwy BC. Got to Kamloops BC about 300km from away. Left Kamloops at around 3pm and it was about 34C then. Driving up a steep hill wife wanted the AC on, at the top of the hill (about 2km long) saw the temp go up two bars. I've had to happen on this same road two days after a bought the car about 3 months ago. So I knew it would happen. I had to run into a store before I left town. Drove for about 1/2 KM to the start of the main highway. Its pretty steep hill. This time the AC was off. About 2.5km up I saw the temps raise so I took my phone and recorded a video. I was at about 80KM/h I didn't get a video of the alarm going off as I had to slow down as there was no where to pull over. The alarm lasted a second and the temp dropped one bar when I shifted to 6th and about 60km/h. Made up to the next exit about 2KM to get gas.

So leaving town its a bit steep but not bad, driving around 90km/h I was keeping it easy, the temps went up two bars. I left it in 6th and just drove at 90. After some time I started to get with the traffic and was at about 110KM/h which is the speed limit. All the way to Merritt about 45 min it was ok. I didn't take the Coquihalla but took another highway from Merritt to Spences Bridge. So this is a pretty windy road and some inclines. The temps outside were 36-38C. I wanted to see if I could get the car temps to go up and I couldn't. They stayed normal.

So I go to Spences Bridge were it was 38C and got onto the Fraser Canyon/Trans Canada. The hill here were way steeper than in Kamloops and I was going about 110/120. The temp bars never moved at all. Not sure way as it was 4+C hotter than when the car did.

Screeshot from the video right before i had the alarm go off. One thing for sure if I lived in Kamloops and I had this car, it would be useless to drive as it would overheat non stop on the hills.
 


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I blasted the Coke 2 weeks ago at 150 the whole way during the day with a Strat tune and didn't see over 230ish? On my access port. There has been talk of faulty or bad-batch rads, hopefully the guys can do something for you. Like I said, if it sets a code it's about 10 easy steps down a ppt to call the rad and replace it. If it set an alarm it legitimately overheated and there will be a code. P2017, IIRC? Something like that. Can't see it on an access port, but it shows up on the ids. I set mine going to Princeton one day in July, and it set a code as described.

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There has been talk of faulty or bad-batch rads, hopefully the guys can do something for you. Like I said, if it sets a code it's about 10 easy steps down a ppt to call the rad and replace it. If it set an alarm it legitimately overheated and there will be a code. P2017, IIRC? Something like that.
Hopefully the video gets some action from the Ford shop, if this was my Bronco and all iron block/heads I wouldn't really care much but I drive to the interior a lot in the summer and plan on keeping the ST for 10+ years so obviously have no desire for warped heads or block because I like to drive the COQ in 30C weather.
 


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For sure. I don't blame you. I plan on getting the mountune rad when I can, but I am 100% in agreement that we shouldn't be having this issue. FWIW, the escape has heat management issues as well, with the same engine. No idea how the factory tune stacks up to the fist though.

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There's a bad batch of fan relays in Fiestas too, so the fan doesn't kick into high when it's supposed to. Worth checking.
 


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Can you be more specific on the Mountune install? I'm planning on getting one. What problems did you encounter, and what all did you have to remove to get the radiator out? Was it true drop in?
I recently installed the Mountune radiator on my 2016 FiST and wrote up some notes and posted pictures on this thread that might be helpful. The short version: it took 8.5 hours; it was a one-person job except for reattaching the crash beam/intercooler assembly, which two friends helped me with; it was a 100% drop-in upgrade; and the radiator solved my cooling problems completely.
 


Erbarry

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I recently installed the Mountune radiator on my 2016 FiST and wrote up some notes and posted pictures on this thread that might be helpful. The short version: it took 8.5 hours; it was a one-person job except for reattaching the crash beam/intercooler assembly, which two friends helped me with; it was a 100% drop-in upgrade; and the radiator solved my cooling problems completely.
I was hoping to get this radiator on sale during Labor Day but the code they had didn't work in it so I'm going to wait for Black Friday. Wouldn't it be easier to drop it from under the car?
 


jayrod1980

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I did it through the bottom... and depending how old or dirty (I clean my car a lot), it's a bear. Without taking off the crash bar you have to deal with pretty cramped conditions. Wear eye protection and gloves especially if you plan on removing through the bottom, and jack the front end up as high as you can. It's difficult to get in without at least bending a couple fins. Also the Mountune radiator has tabs in the top and bottom that are only plastic on the stock radiator. I suggest you loosen the bolts prior so that you can get everything lined up before you attempt to get the tabs hooked onto the radiator fan shroud. You must remove your cold side charge pipe, and I suggest removing your headlights as well. Even if you take it out from the bottom, you want as much visual room as possible. Fins are very easy to bend... just a touch on anything is going to fold them over. Despite the pain, it's an amazing radiator. I'm not sure if my stock one was defective or just insufficient, but the new one works 200% better. In constant, above 100F heat I've not even gotten within 30 degrees of the old one in the same conditions... and it sheds heat really fast even when it does get warm. I have yet to test it in a track environment, but harsh stop and go in 110F hardly taxes it. I am however using a 70/30 water to coolant mix.
 


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I was hoping to get this radiator on sale during Labor Day but the code they had didn't work in it so I'm going to wait for Black Friday. Wouldn't it be easier to drop it from under the car?
It sounds like removing it from underneath is possibly more difficult in the sense that it is very cramped and you're on your back and it's easier to bend and bang things that don't want bending and banging. But there is less disassembly than removing the front of the car (and so less time consuming?). So it's probably personal preference; it was worth it to me to take a day to pull everything apart because then I had easy access to everything.
 


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Dropped it off at the dealer and showed them the video. They saying no codes and all tests out fine. They asked to keep the car overnight and requested special tech support from Ford.
 


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Good deal; keep us posted.
Well that got no where. I guess if they don't see it themselves nothing is wrong and apparently the overheat alarm didn't trigger any codes. I got a solution though, just gonna cancel my extra warranties and keep the money in the bank for any repairs that pop up and just buy an after market rad lol. Problem solved
 


Truth in Ruin

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Well that got no where. I guess if they don't see it themselves nothing is wrong and apparently the overheat alarm didn't trigger any codes. I got a solution though, just gonna cancel my extra warranties and keep the money in the bank for any repairs that pop up and just buy an after market rad lol. Problem solved
I'm pretty sure it is the radiator. Sounds like a good plan, but I'm disappointed in the dealership you went to.
 


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I got a solution though, just gonna cancel my extra warranties and keep the money in the bank for any repairs that pop up and just buy an after market rad lol. Problem solved
I think that's sensible. The aftermarkets rads seem to have a high success rate.
 




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