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2016 fiesta st overheating

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So mountune radiator is in and so far it's impressive. Took it on a hour driver with ac on and it barely peaked 190.8 on the accessport. But my stock radiator had a whole bunch of debris between the ac condenser and radiator.




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jayrod1980

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The Mountune is impressive. I sat in my car in 109F with the A/C blasting at 70 for 20mins and finally got coolant up to 206F. As soon as I pulled away it went back down to 190F... in literally 2 mins. This radiator can handle anything. With temps as high as 110F I still haven't hit 200F while in motion. When I get the oil cooler installed I think it will be even better. It's definitely a good product. Just a pain to install.
 


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Saw 215 on my 9 hour drive. My coolant on the other hand never went over 198


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I've only got the MISHI oil cooler and stock rad and I never see temps above 210 oil and 195 coolant...just daily driving no track.
Wonder if I have a lucky radiator?
 


jayrod1980

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I see 216F max for oil with the Mountune installed and stock oil cooling element. Doesn't seem to matter what coolant temp is for me with respect for oil unless coolant temps go above 210F. At 80mph I hit 216F max on oil.
 


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I've only got the MISHI oil cooler and stock rad and I never see temps above 210 oil and 195 coolant...just daily driving no track.
Wonder if I have a lucky radiator?
I see 216F max for oil with the Mountune installed and stock oil cooling element. Doesn't seem to matter what coolant temp is for me with respect for oil unless coolant temps go above 210F. At 80mph I hit 216F max on oil.



What weight oil and filter are you using? And what brand?

Might be thermal efficiency difference between different oils with the base stock in the oil. I know I run castrol 5w-20 full synthetic which is mostly PAO and ester base stock


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What weight oil and filter are you using? And what brand?

Might be thermal efficiency difference between different oils with the base stock in the oil. I know I run castrol 5w-20 full synthetic which is mostly PAO and ester base stock


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Filter: Switched from the NAPA platinum back to the Motorcraft FL400-S. But will probably go back to Napa.
Oil: Castrol Edge Syntec
 


Intuit

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Yay! I got my car back on Aug 6th! The dealer replaced the radiator, fan relay and a joint.
Car seems ok. Went over 210 in 80 degree weather when I hit some traffic, but I attributed this to the previous 50 plus miles at 70 mph. It did cool down to 188-194 range.
If you dont have an accessport for accurate temp readings invest in the bluetooth OBD reader and whatever app you need to support it.
The little row of blue lights is worthless. 188 to over 200 and no change in the display.
Anyway, it was different driving the '17 Fusion Hybrid. A constant moaning sound unless youre on electric, then LOOK OUT 4 PEDESTRIANS!
People staring at their phones walk right in front of you.
Loud pipes save lives!!!!!
Meh, Darwin is slowly sorting it out. [wink]
For the reason you mentioned, EU has regulations that mandate vehicles make a certain level of noise that the manufacturers must meet.

All stock. With limited monitoring, it seems to settle and stabilize around 192 in mixed driving, extended idling. Haven't yet monitored in traffic jams as I tend to avoid them. Ambient temps in the mid-eighties, mild humidity, winds out of North, 550ft elevation.

The last vehicle I drove daily had a stock full open temp of 192°F. Most vehicles I've paid any close attention to, stabilize within so many degrees of the specified thermostat open temp. My motorcycle stabilizes at 176°F, with an open range of 160-185°F.

The Fiesta on the other hand is different. While it starts to open at 180°F it is not fully open until a whopping 207°F. My 192°F stabilized is a degree or so on the cooler from the middle. The middle temp ~194°F.

Also note, that the manual specifies that the cooling system be vacuum filled. Even after that, it still has you run through five 30 second run cycles to complete the bleeding process.

I've been perusing the manual in an attempt to locate the engine fan on/low/high/off temperatures but have so far been unsuccessful.
 


jayrod1980

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For oil I'm sure elevation and temperature have some value. When I hit 216F it's when I'm on the throttle, in boost, at 80mph+ in 100F or more. Much of my drive is chugging up elevation. If I were to average it out, it's actually probably at 208-210F. Both the Mountune and stock radiators make no difference on this reading. When my oil radiator would start to overheat though, oil temps got hot fast!

I use the motorcraft Fl-400S filter and Castrol Edge 5W-20. No matter what oil I use it always comes out looking like black stinky oil because of the blow by. I might try Rotella next time but typically O'Reilly has a good deal on Edge when I go in.
 


Intuit

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Yeah that sounds like right where the 'stat is full open. Higher elevation means less air-density, which makes cooling notably less efficient.

Whether I'm hard on the accelerator or not doesn't seem to make much of a difference on peak; just how quickly it heats up.

The Motorcraft FL-400S was the stock filter for my '94 Ford Escort, a 1.9L Single Overhead Cam with a massive 88hp. How large the filter is, may not be the only characteristic to look at. What are the flow characteristics and MTFB specifications for example?
 


M-Sport fan

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The Motorcraft FL-400S was the stock filter for my '94 Ford Escort, a 1.9L Single Overhead Cam with a massive 88hp. How large the filter is, may not be the only characteristic to look at. What are the flow characteristics and MTFB specifications for example?
AGREED. [thumb]

But, many on here have used these for many miles with no noticed 'ill effects' (and yes, I know that does NOT prove that they are optimal ;) ).

Also, IF you trust Mountune's engineering judgement AT ALL (MANY on here do not it seems, going by the all-out, animus-driven flame wars in other threads about their MRX kit [:(]), they have the 400-S for sale right on their site as the ONLY replacement oil filter they sell for this app. [dunno]
 


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jayrod1980

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I heard the filter was redesigned. At any rate, the 400 is bigger than the stock oil filter. Nothing wrong with that. One of those oil review sites cut this filter and others to compare... it did well. I think some other company makes them for ford anyway. All I know is that it's the biggest filter I can fit between the MAP cold side pipe and this new radiator.

I don't know about Mountune's other stuff but this radiator (which is made by CSC or someone) is so much better than stock! I haven't seen anyone post numbers in triple digit numbers of the Mishimoto that are any better. They seem to do similar, but without the added size and modification needed. Car doesn't even approach 200F for coolant even in 110F heavy traffic.
 


M-Sport fan

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I don't know about Mountune's other stuff but this radiator (which is made by CSC or someone) is so much better than stock! I haven't seen anyone post numbers in triple digit numbers of the Mishimoto that are any better. They seem to do similar, but without the added size and modification needed. Car doesn't even approach 200F for coolant even in 110F heavy traffic.
The company which Mountune sub-contracts for their radiators is CSF.

That is great to hear about this radiator, since it is the aftermarket one I will go to if/once I start having problems with the factory unit [thumb] (which might be sooner than later since so many on here claim that the cp-e IC will not allow enough flow-through air to the factory radiator, raising coolant temps, due to it being bar and plate construction [:(]).
 


jayrod1980

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Sorry, I got the acronym for the manufacturer wrong. It's very pretty in person. I can tell you, the MAP cold side pipe is very berry... stainless steel and it sits directly against the fan shroud with this intercooler. I can only imagine how much the shroud, even in aftermarket configuration, would butt against the cold side charge pipe. With the Mountune radiator, I will sand down the shroud an inch or so (it's about 2 inches thick at that point). Everything is okay already but it seems like vibrations are worse because the shroud butts against the cold pipe, which is bolted to the engine. Coupled with the Cobb motor mount, vibration feels worse, but then again, in hot conditions my A/C is running all the time... which makes vibrations harsh. I'll let you know if sanding down the shroud near the pipe helps. I couldn't imagine how much the mishi radiator and shroud interfere with aftermarket charge pipes, considering the size difference of the mishi vs the Mountune.
 


Intuit

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I heard the filter was redesigned. At any rate, the 400 is bigger than the stock oil filter. Nothing wrong with that. One of those oil review sites cut this filter and others to compare... it did well. I think some other company makes them for ford anyway. All I know is that it's the biggest filter I can fit between the MAP cold side pipe and this new radiator.

I don't know about Mountune's other stuff but this radiator (which is made by CSC or someone) is so much better than stock! I haven't seen anyone post numbers in triple digit numbers of the Mishimoto that are any better. They seem to do similar, but without the added size and modification needed. Car doesn't even approach 200F for coolant even in 110F heavy traffic.
I noticed the changes when they redesigned the filter. [smile] Based upon my photo, that was probably 2009 or 2010. The redesigned filter was actually smaller...
https://1drv.ms/i/s!AhsZJDCN8kMMgkDXlz9zT1IwaxHf
http://www.feoa.net/threads/1998-zx2-filter-and-oil.83170/#post-737602
http://www.feoa.net/threads/motorcraft-serpentine-belt-tensioner.72951/page-2#post-665113
...as my comments above point out, bigger is not always better. (particularly if you change your oil often) It is certainly possible that another refresh was done since then; changes not being so obvious this time around. In any regard, reportedly Ford still warranties the powertrain even with specific Mountune kits and M-Sport says Mountune vetted the filter. So it's probably all good.
 


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This is a typical ~25mi trip(highway w/ cruise set @ 70mph) for me. Data collection purposes only:
IMG_2996.JPG

Even when ambient temps are upto 20-25 degrees higher it pretty much logs identically except for the C/IAT's.
 


alexrex20

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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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