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Engine cuts power sometimes when accelerating through corners?

Waterfan

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#1
~400 miles of experience on my 'new' 2014 CPO now (90% of those 400 purely for the fun of it - SoCal canyons nearby). I'm getting fairly comfortable with this amazing little car (the torque vectoring pulling the rear end around in sharp turns is giggle-inducing fun). At this point I have only one "complaint".

I feel like the engine momentarily cuts power in and out sometimes when accelerating hard through corners (ECS Off). I feel it most on 90deg right handers so far. Sometimes with or without noticable wheel spin.

It makes the car feel jerky, I don't care for the unpredictability and how it unsettles the car. I'd rather feel the start of understeer and lift off the gas my own self.

Am I right that it is the engine briefly cutting power in and out automatically? If not, what is the cause? Whatever it is called, is there a way to disable it? Or is the car going to force me to learn how to drive right? (proper slow(er) in, fast out)

And/or any other advice to deal with what I'm experiencing?
 


OP
Waterfan

Waterfan

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Thread Starter #3
Thank you for the feedback.

Low 70s today, driving ~6/10ths or less on the street, accelerating ~3/4rds throttle for less than 5 seconds? It had better NOT be heat soak in these mild conditions.

Is the FiST really that poor at heat management?
 


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#4
Are you pressing the traction control button once, or holding it down while the little loading screen displays on your radio screen? For it to be truly off you have to hold it down, and wait for the loading bar to complete.
But yes, the factory intercooler isn't very effective at all.
 


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#5
I have been experiencing the same thing every once in a while. It has never occurred to me that it was the traction control kicking in, but that makes sense. I will make sure and turn it off next time (hold down for loading bar) and I'm sure it will fix it.[thumb]
 


C. love

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Are you pressing the traction control button once, or holding it down while the little loading screen displays on your radio screen? For it to be truly off you have to hold it down, and wait for the loading bar to complete.
But yes, the factory intercooler isn't very effective at all.

I 100% agree with everything said here.
 


OP
Waterfan

Waterfan

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Thread Starter #8
Are you pressing the traction control button once, or holding it down while the little loading screen displays on your radio screen? For it to be truly off you have to hold it down, and wait for the loading bar to complete.
But yes, the factory intercooler isn't very effective at all.
thank you

Yes, I am positive ECS is disabled (after holding the button for 7-10s), not just in Sport. Yes, the button is REALLY touchy. You have to be sure to press it firmly and let it go smoothly or you might just end up in normal or sport.

So this really might be heat soak? even in these mild conditions?
 


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#9
Could possibly be the torque vectoring, you can't turn that off even if you have ESC disabled.
 


D1JL

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#10
Could possibly be the torque vectoring, you can't turn that off even if you have ESC disabled.
As per the description from Ford, torque vectoring does NOT slow the car.
I would think that cutting the engine would slow the car.

Here is a wild thought however.
How much gas do you have in the tank?
Is it possible that the fuel is sloshing away from the pickup tube.

I have driven most all if the mountain/canyon roads in So. Cal.
At many times I have driven them in a VERY spirited manor and I have never experienced this.
I also never let my tank get below quarter full and very rarely let it go below half.


Dave
 


OP
Waterfan

Waterfan

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Thread Starter #11
As per the description from Ford, torque vectoring does NOT slow the car.
I would think that cutting the engine would slow the car.

Here is a wild thought however.
How much gas do you have in the tank?
Is it possible that the fuel is sloshing away from the pickup tube.

I have driven most all if the mountain/canyon roads in So. Cal.
At many times I have driven them in a VERY spirited manor and I have never experienced this.
I also never let my tank get below quarter full and very rarely let it go below half.


Dave
Good thought, but 3/4 tank when I last felt the behavior...
 


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#12
There is no way this is heat soak driving the way he is describing.


I believe that the torque vectoring is never COMPLETELY off, even when holding the button down for 7 seconds. Consult your manual. basically same thoughts as Instwin
 


OP
Waterfan

Waterfan

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Thread Starter #13
There is no way this is heat soak driving the way he is describing.


I believe that the torque vectoring is never COMPLETELY off, even when holding the button down for 7 seconds. Consult your manual. basically same thoughts as Instwin
I agree that Torque Vectoring Control (TVC) is never fully disabled. But the Fiesta ST's TVC is a braking-based system and would not cause the engine to lose power/hesitate.

According to Ford's TVC video (https://www.youtube.com/watch?v=dc4I1DSqD8o), TVC aids turning by braking the inside wheel whereas Traction Control reduces engine torque.

I'm going to rule this as Operator Error (me) for now and apologize for the wild goose chase. Despite convincing myself that ECS was Disabled, I'll bet that even though it said "ECS Disabled", it accidentally slipped into Sport and I didn't notice because letting off the button is very touchy.

Does the Cobb AP (or any other method) allow you change the default traction mode on startup? My finger cannot be trusted and I wouldn't mind saving 5-10s every startup NOT using that problematic button.

Thanks all.
 


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#14
I'm going to rule this as Operator Error (me) for now and apologize for the wild goose chase. Despite convincing myself that ECS was Disabled, I'll bet that even though it said "ECS Disabled", it accidentally slipped into Sport and I didn't notice because letting off the button is very touchy.
Don't beat yourself up too quickly. Run it again,be deliberate w/ the ecs,and post an update.
 


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#16
Just wanted to add my 2 cents here. I have noticed the same thing happen, left and right and turns under hard acceleration, with sport mode or traction control on, the engine does cut power. I haven't tried a turn with traction control fully off though, I'll give that one a shot and see if I notice a difference.
 


OP
Waterfan

Waterfan

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Thread Starter #17
Just wanted to add my 2 cents here. I have noticed the same thing happen, left and right and turns under hard acceleration, with sport mode or traction control on, the engine does cut power. I haven't tried a turn with traction control fully off though, I'll give that one a shot and see if I notice a difference.
I'm back from more testing :)

ECS Disabled (press and hold for 5-10s) makes a BIG difference. Normal or Sport, it feels like the power disappears abruptly and then slams back in abruptly. ECS Disabled, the sense of "loss" is far, FAR less dramatic. It may only be the sensation of the TVC (brake vectoring) kicking in AFTER wheelslip has already occurred. Or that is how it felt to me 10 mins ago, running the same few corners back-to-back, trying to match speed, in the different modes.

Ford did a great thing, IMO. I HATE the Traction Control (Normal or Sport) but LOVE Torque Vectoring (TVC, all modes). Now if I could just set it to ECS Disabled on startup by default my "life would be perfect". :)
 


haste

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#18
The only time I have noticed this is with ESC not off. I've done track sessions with it completely off and never lost power during cornering. I have yet to try sport mode. I'm either fully on or fully off.
 


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#19
I'm back from more testing :)

ECS Disabled (press and hold for 5-10s) makes a BIG difference. Normal or Sport, it feels like the power disappears abruptly and then slams back in abruptly. ECS Disabled, the sense of "loss" is far, FAR less dramatic. It may only be the sensation of the TVC (brake vectoring) kicking in AFTER wheelslip has already occurred. Or that is how it felt to me 10 mins ago, running the same few corners back-to-back, trying to match speed, in the different modes.

Ford did a great thing, IMO. I HATE the Traction Control (Normal or Sport) but LOVE Torque Vectoring (TVC, all modes). Now if I could just set it to ECS Disabled on startup by default my "life would be perfect". :)
Good to hear!
 


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#20
I'm experiencing this but my OAR reads 0.60 when the power is cut. Then after cruising for awhile, like, at least 5 minutes, the OAR returns to -1.00. Only occurs during steepish declines and any moderate to aggressive turns, left or right. But the latter doesn't have to be on a decline, roundabouts are sufficient for this to happen to me.
Thinking it's more a fuel issue than the ESC button, but never tried turning the ESC all the way off either. The reason I believe it's the former is cuz of the OAR.
Any assistance would be greatly appreciated. Thanks.
 




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