• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Explorer ST Forum and Explorer ST community dedicated to Explorer ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Explorer ST Forum today!


Transmission/Shifting Stall !!!!!!!

Messages
39
Reactions
28
Points
2
Location
Parkton, MD, USA
#1
I have recently brought my ST in for what I perceive to be a fairly significant transmission/shifting issue.

The issue happens often when I’m attempting to pass someone. Keep in mind, we all have a high performance and very fast vehicle. :)

If you accelerate as if you’re about to pass, let off the gas suddenly (in my case where I can’t quite pass yet), and then hit the gas hard...the vehicles loses all its powers/hesitates/and almost feels like The engine is stalling.

I can reproduce this every time now but the dealership is telling me nothing is wrong. This almost got me killed the first few times when I had no idea what was going on and I’ve never experienced this in the car before. Now I have to be somewhat gentle when I accelerate or pass a car in my $60k sport tuned vehicle??? WTF?

Has anyone experienced this? Can anyone also simulate or reproduce this?

I’m sorry Ford but this is a big issue and it needs to be addressed.


Sent from my iPhone using Tapatalk
 

Messages
286
Reactions
114
Points
37
Location
Cincinnati, OH
#2
Sorry to hear that, does it happen in all drive modes?
 

OP
C
Messages
39
Reactions
28
Points
2
Location
Parkton, MD, USA
Thread Starter #3
Yes, it doesn’t matter what drive mode I am in. Are you saying this doesn’t happen to you at all and that you can’t force this to happen?


Sent from my iPhone using Tapatalk
 

Messages
286
Reactions
114
Points
37
Location
Cincinnati, OH
#4
Yes, it doesn’t matter what drive mode I am in. Are you saying this doesn’t happen to you at all and that you can’t force this to happen?


Sent from my iPhone using Tapatalk
I've never experienced any power loss after taking my foot off the gas and step on the accelerator again to the point where it feels like stalling. That's really scary. I wonder if you can reach out to Ford and have a regional manager look at it or take it to another dealer.
 

OP
C
Messages
39
Reactions
28
Points
2
Location
Parkton, MD, USA
Thread Starter #5
I recall the technician telling me something about the throttle body and how it needs time to open and close if you suddenly gas it, let go of the gas momentarily, and then gas it again. Still, this should never happen what I’m experiencing.


Sent from my iPhone using Tapatalk
 

STFan

Administrator
Messages
746
Reactions
351
Points
182
#6
I bet the stalling and loss of power your experiencing is the excess fuel in the chamber that wasn’t burned because there wasn’t enough air getting through when you let off the gas. Either way it’s still very scary in real world driving.
 

Messages
114
Reactions
48
Points
27
Location
North Hampton, NH, USA
#7
Try another dealer. Better yet, try another st from your current dealer.
Not sure why you would stab it without assurance of a clear lane but.....
 

OP
C
Messages
39
Reactions
28
Points
2
Location
Parkton, MD, USA
Thread Starter #8
Not even stabbing it....just accelerating...doesn’t matter how much gas you give it. Shocked nobody had this issue given my dealer said this is “normal”. I will try another dealer. Thanks!


Sent from my iPhone using Tapatalk
 

STO

Member
Messages
27
Reactions
6
Points
2
Location
Warner Robins, GA, USA
#9
Have you owned a turbo vehicle before?
 

OP
C
Messages
39
Reactions
28
Points
2
Location
Parkton, MD, USA
Thread Starter #10
No, this is my first.


Sent from my iPhone using Tapatalk
 

Messages
17
Reactions
3
Points
2
Location
Jersey Shore, PA, USA
#11
Any update on this? I'm going to go give this a try. We have a '21 ST with 5700. My wife complained of something similar, only difference, our ST will tell her to pull over and restart the engine. She also stated the auto start light on the dash flashes when it happens. She can't recreate it on demand and hasn't yet figured out what she is doing when it happens. It's never happened to me and I drive it more then her. Last happened while merging on to the highway. We took it to the dealer and they also couldn't reproduce and it isn't logging an error.
 

TMac

1000 Post Club
Messages
1,691
Reactions
1,449
Points
262
Location
Knoxville, TN
#12
There are a lot of things going on mechanically that take time when you do this depending on speed and demand:

1. ECU "sees" demand via accelerator pedal
2. "demand" transmitted to CAN bus
3. ECU uses appropriate map to open throttle body and alter cam position to max torque. Throttle body with variable camshaft tuning is NOT linear, thus the reason you see the DBW throttles with variable cams.
4. TCM sees "demand" from CAN bus, and (depending on condition) unlocks torque converter and downshifts appropriately and may adjust duty cycle on AWD clutches
5. Vehicle accelerates.

Now a lot of stuff is going on and it takes time. Now you let off, possibly dramatically, and most of this happens in reverse order. However you're now going faster and you repeat acceleration event so possible explanations :
The ECU/TCU may simply be slow to respond to another event in succession
The ECU/TCU may be programmed to limit response to immediate, dramatic changes in demand for any number of reasons
Torque converter unlock, lock, unlock may be slow and may not happen at all.

SInce you're moving faster, the demand may not be seen as extreme as before so response is delayed
There are so many possibilities in this scenario, that I would likely guess it's probably both limited in response time, and in being able to readjust all the above mechanical parts in such quick succession. There could also be ECU/TCU strategies to limit torque output in such a scenario.

You might try doing this in Manual mode to see if you have the same issues. But, to be honest, this isn't a big torquey V8 mounted to a manual transmission and a direct wired throttle. Unless it throws a code the average tech is going to tell you it's normal.
 

OP
C
Messages
39
Reactions
28
Points
2
Location
Parkton, MD, USA
Thread Starter #13
I have noticed that this problem cannot be recreated in sport mode. But it does happen in every other mode. It just means that I have to be more conscious about my driving style and be much more gingerly if I’m not in sport mode.


Sent from my iPhone using Tapatalk
 

TMac

1000 Post Club
Messages
1,691
Reactions
1,449
Points
262
Location
Knoxville, TN
#14
It would make sense that Sport mode doesn't do this, as the some of those steps are not being taken, for example letting off in Sport applies engine braking- meaning the engine didn't immediately unlock the torque converter and upshift some number of gears. Therefore you don't get all the same hesitation when you floor it again. I thought I read above it did happen in Sport mode.
 

robs90

New Member
U.S. Navy Veteran
Messages
3
Reactions
4
Points
2
Location
San Diego, CA, USA
#15
I have recently brought my ST in for what I perceive to be a fairly significant transmission/shifting issue.

The issue happens often when I’m attempting to pass someone. Keep in mind, we all have a high performance and very fast vehicle. :)

If you accelerate as if you’re about to pass, let off the gas suddenly (in my case where I can’t quite pass yet), and then hit the gas hard...the vehicles loses all its powers/hesitates/and almost feels like The engine is stalling.

I can reproduce this every time now but the dealership is telling me nothing is wrong. This almost got me killed the first few times when I had no idea what was going on and I’ve never experienced this in the car before. Now I have to be somewhat gentle when I accelerate or pass a car in my $60k sport tuned vehicle??? WTF?

Has anyone experienced this? Can anyone also simulate or reproduce this?

I’m sorry Ford but this is a big issue and it needs to be addressed.


Sent from my iPhone using Tapatalk
I know this is an older post but had my 2021 new Ford Explorer ST stalling out on the highway (in sport mode) while trying to make a pass during heavy traffic (only to have my Explorer bog and stall when I would floor it multiple consecutive times in a row). This could have killed someone!!!! I ended calling Ford Customer Care about it (knowing my local dealer is hit and miss), which turned out to be the best way to go. The first call I received from my service advisor was "There are no error codes and we were not able to reproduce the problem." Ford ended up engaging their top engineering team to assist the local dealership. They were able to duplicate this issue through an advanced road test (the dealer said it was called a "wiggle test") where they would jiggle certain wires while accelerating on the highway. From there, they replaced the "Gateway Module" but must have been able to reproduce the problem as there was another electrical component that worked with the ECU that they replaced. I was down for almost 4 straight weeks but got a call from Ford letting me know that the car is ready and good to go. I wanted to share my story here as I seen others having this problem as well.

Rob
 

Messages
121
Reactions
61
Points
27
Location
Canada
#16
I’ve been going through the exact same thing for almost a year now!
crusing at highway speed, hit the gas, bogs down loses power! In and out of service, “no codes, nothing wrong (yeah right) can’t reproduce it”
Finally had enough after lost total power and wouldn’t even accelerate when in gear, like it was in neutral but clearly was in gear!
it’s in the shop today they gonna rip the whole transmission apart. Was wondering when I’d see someone else post similar!!
 

Attachments

Messages
121
Reactions
61
Points
27
Location
Canada
#17
I’ve been going through the exact same thing for almost a year now!
crusing at highway speed, hit the gas, bogs down loses power! In and out of service, “no codes, nothing wrong (yeah right) can’t reproduce it”
Finally had enough after lost total power and wouldn’t even accelerate when in gear, like it was in neutral but clearly was in gear!
it’s in the shop today they gonna rip the whole transmission apart. Was wondering when I’d see someone else post similar!!
 

TMac

1000 Post Club
Messages
1,691
Reactions
1,449
Points
262
Location
Knoxville, TN
#19
I’ve been going through the exact same thing for almost a year now!
crusing at highway speed, hit the gas, bogs down loses power! In and out of service, “no codes, nothing wrong (yeah right) can’t reproduce it”
Finally had enough after lost total power and wouldn’t even accelerate when in gear, like it was in neutral but clearly was in gear!
it’s in the shop today they gonna rip the whole transmission apart. Was wondering when I’d see someone else post similar!!
I don't think @sleekone problem is the same as the original poster's problem. It doesn't seem like the car "bogs", from what I can tell from the video, looks like bands are completely slipping, it's not shifting correctly at all. That doesn't mean they aren't related to some electrical problem somewhere, but the conditions seem to be different.
 

Messages
121
Reactions
61
Points
27
Location
Canada
#20
I don't think @sleekone problem is the same as the original poster's problem. It doesn't seem like the car "bogs", from what I can tell from the video, looks like bands are completely slipping, it's not shifting correctly at all. That doesn't mean they aren't related to some electrical problem somewhere, but the conditions seem to be different.
2 separate symptoms. Bogs down at shifting on highway but then also had the issue in the video last week which I was able to catch on my phone and send to the dealership.
 



Top