2019 10R80 GT - Sticking throttle/acceleration at low speeds?

saiyangt

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Hi there everyone, I'm hoping you can help me diagnose an issue I'm having.
So far 3 dealers I've taken the car to haven't been able to replicate the issue, but it's certainly there.

My car will periodically continue to accelerate on its own.
It's always at low speeds, and happens exclusively in low gears (primarily 1st and 2nd).
It's especially bad when cold - almost every morning when I first accelerate, if I let off the gas the car will continue accelerating at a moderate speed for 1 - 1.5 seconds.
It only happens the first 1-2 times each morning/cold start. Sometimes it won't happen at all, but it does more often than not.

Since the conditions for replicating the issue are kind of tricky, no Ford dealer has been able to replicate. I will ask for a technician to ride with me so that I can drive it myself and show them - In the mean time I'm looking for your guidance.

The dealer did, however, check the transmission oil levels and inspected for contaminants - Both of which were fine.
They also stated they used monitoring software to view transmission behaviour while driving and found it normal.

I'm kind of at a loss now in terms of what this could be. Surely something this unsafe can't be normal behaviour of the car.

What could this be?
Dirty/failing throttle body? Throttle body position sensor? Undiagnosed transmission issue?

Any help would be much appreciated!





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ice445

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It's the throttle doing that. It holds itself open sometimes when the car deems it necessary. I have a manual car, but in my case the RPM drops extremely slowly on the first few shifts of the day. I think it's cat warming behavior, but I could be wrong. In your case it seems like it's not quite right though.

Could also be a defective PCV Valve. Those are cheap and easy to replace.
 

wade001

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happens on my 19 gt as well, very noticeable when cold, ie: first start of the morning, and driving through the parking lot slowly as not to get rpms too high and wake up everyone or scare the dog/dogwalkers in the early morning

it seems to me, to be transmission related. the car wants to hold gears longer when cold and those first few shifts. from my understanding this is normal.

the car will, most definitely, accelerate MORE after i let off the gas, but i find its really only so it can shift to the next gear (a few hundred rpm more), at which point it doesnt accelerate any longer. first few times it happened, it didnt seem right to me either, but if you were to ask me now, i'd say its normal..
 
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saiyangt

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happens on my 19 gt as well, very noticeable when cold, ie: first start of the morning, and driving through the parking lot slowly as not to get rpms too high and wake up everyone or scare the dog/dogwalkers in the early morning

it seems to me, to be transmission related. the car wants to hold gears longer when cold and those first few shifts. from my understanding this is normal.

the car will, most definitely, accelerate MORE after i let off the gas, but i find its really only so it can shift to the next gear (a few hundred rpm more), at which point it doesnt accelerate any longer. first few times it happened, it didnt seem right to me either, but if you were to ask me now, i'd say its normal..
This is exactly what mine does as well. It seems strange though, I've never experienced this in any other car, nor have I heard of it happening in any other car. I could very easily see a class action lawsuit resulting due to the car accelerating without the drivers input... If this really is considered normal operation then I'm quite disappointed in Ford to be honest.
 

JimGT

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My 2018 does exactly the same since new. I agree it is dangerous but like most things it is a waste of time to chase it with a dealer.
 

IrishStallion

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Mine will actually flash the converter occasionally when cold around 15 mph. It spins up to 4500 rpms for a second or two. Scares the crap out of me when your foot is off the accelerator and on the brake. This car in one funky mess. If it did not run so well at wot I would have flipped out of it 1.5 years ago. lol.
 
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saiyangt

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Im not sure where i recall reading this..but maybe its worth a shot.

Try pulling the fuse for the cruise control and see if that helps it any?
I'll give it a go! I'm not sure why cruise would interfere in such a strange way. Although, I guess that adaptive cruise control does have direct control over the cars throttle and brakes to a degree - worth a shot!

Car is away for storage for the winter, I'll try in the spring. Thanks!
 
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saiyangt

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Mine will actually flash the converter occasionally when cold around 15 mph. It spins up to 4500 rpms for a second or two. Scares the crap out of me when your foot is off the accelerator and on the brake. This car in one funky mess. If it did not run so well at wot I would have flipped out of it 1.5 years ago. lol.
When you say "flash the converter" what exactly do you mean?
Apologies, I'm not overly mechanically inclined. I'm assuming that you mean the car's torque converter - but I'm not familiar with the term "flashing".
 

Synergy720

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Hi there everyone, I'm hoping you can help me diagnose an issue I'm having.
So far 3 dealers I've taken the car to haven't been able to replicate the issue, but it's certainly there.

My car will periodically continue to accelerate on its own.
It's always at low speeds, and happens exclusively in low gears (primarily 1st and 2nd).
It's especially bad when cold - almost every morning when I first accelerate, if I let off the gas the car will continue accelerating at a moderate speed for 1 - 1.5 seconds.
It only happens the first 1-2 times each morning/cold start. Sometimes it won't happen at all, but it does more often than not.

Since the conditions for replicating the issue are kind of tricky, no Ford dealer has been able to replicate. I will ask for a technician to ride with me so that I can drive it myself and show them - In the mean time I'm looking for your guidance.

The dealer did, however, check the transmission oil levels and inspected for contaminants - Both of which were fine.
They also stated they used monitoring software to view transmission behaviour while driving and found it normal.

I'm kind of at a loss now in terms of what this could be. Surely something this unsafe can't be normal behaviour of the car.

What could this be?
Dirty/failing throttle body? Throttle body position sensor? Undiagnosed transmission issue?

Any help would be much appreciated!
These cars tend to do that when you do a first start in the morning when its not hot. Mine would do the same exact thing. It seems to be only with the automatics. My buddy's 19 5.0 manual holds the RPMs for a hot minute when on the clutch shifting. You'll only be able to replicate it when its a literal cold start. But once the car has been running 3-4 minutes you shouldn't have the issue. Unless its super cold.
Just my experience.
 

IrishStallion

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When you say "flash the converter" what exactly do you mean?
Apologies, I'm not overly mechanically inclined. I'm assuming that you mean the car's torque converter - but I'm not familiar with the term "flashing".
Meaning while driving the rpms will suddenly just jump up to 4k rpms like you put the car in neutral. Only does it every once in a while when trans temps are below 100f.
 

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