Throttle Lag

[BamaST]

Hey y'all.

Been lurking the forum for a while now. 2020 ST owner with most of the upgrades y'all recommended. Whipped IC, JLT catch can. No aftermarket tune yet until I'm certain the tranny won't have an issue like some have been experiencing.

So far, I've had the weird clunking from somewhere under the truck. I think that is the gas tank issue. Some hard shifts but I'm an lead foot, so I figured it's my driving style.

However, last week I started having a new problem. At normal speeds, like taking off from a slow right turn or starting up after a stop in traffic, the throttle lags for a couple of seconds before it engages. Almost like limp home mode in other cars but it only lasts for maybe 2-3 seconds. You press the throttle and nothing happens. Just bogs. Then she will finally accelerate.

I've read through just about all the forum posts, but didn't find anything specific. A few mentions of power loss but not sure if that's a related problem.

Anyone else having that issue?
2020 ST, about 5k miles. No tune, just AM Whipple IC. I did double check all the hoses yesterday to make sure a clamp hadn't come loose. It's intermittent though. Always at Low speeds.

 

[BamaST]

My apologies folks. After posting this, the similar threads feature shows me a few threads on this issue. Sorry to be a bother.

 

[Garda934]

No worries and welcome!

 

[hifibrucep]

Hey y'all.

Been lurking the forum for a while now. 2020 ST owner with most of the upgrades y'all recommended. Whipped IC, JLT catch can. No aftermarket tune yet until I'm certain the tranny won't have an issue like some have been experiencing.

So far, I've had the weird clunking from somewhere under the truck. I think that is the gas tank issue. Some hard shifts but I'm an lead foot, so I figured it's my driving style.

However, last week I started having a new problem. At normal speeds, like taking off from a slow right turn or starting up after a stop in traffic, the throttle lags for a couple of seconds before it engages. Almost like limp home mode in other cars but it only lasts for maybe 2-3 seconds. You press the throttle and nothing happens. Just bogs. Then she will finally accelerate.

I've read through just about all the forum posts, but didn't find anything specific. A few mentions of power loss but not sure if that's a related problem.

Anyone else having that issue?
2020 ST, about 5k miles. No tune, just AM Whipple IC. I did double check all the hoses yesterday to make sure a clamp hadn't come loose. It's intermittent though. Always at Low speeds.

What post did you go too. I am having the same lag

 

[StevieB]

I too am having boging issues any suggestions? local dealers- yes both dealers can't figure it out and said it's "normal" to the way I am driving the vehicle. any help would be awesome!!

 

[StevieB]

Hey y'all.

Been lurking the forum for a while now. 2020 ST owner with most of the upgrades y'all recommended. Whipped IC, JLT catch can. No aftermarket tune yet until I'm certain the tranny won't have an issue like some have been experiencing.

So far, I've had the weird clunking from somewhere under the truck. I think that is the gas tank issue. Some hard shifts but I'm an lead foot, so I figured it's my driving style.

However, last week I started having a new problem. At normal speeds, like taking off from a slow right turn or starting up after a stop in traffic, the throttle lags for a couple of seconds before it engages. Almost like limp home mode in other cars but it only lasts for maybe 2-3 seconds. You press the throttle and nothing happens. Just bogs. Then she will finally accelerate.

I've read through just about all the forum posts, but didn't find anything specific. A few mentions of power loss but not sure if that's a related problem.

Anyone else having that issue?
2020 ST, about 5k miles. No tune, just AM Whipple IC. I did double check all the hoses yesterday to make sure a clamp hadn't come loose. It's intermittent though. Always at Low speeds.

I am having these same issues:
(However, last week I started having a new problem. At normal speeds, like taking off from a slow right turn or starting up after a stop in traffic, the throttle lags for a couple of seconds before it engages. Almost like limp home mode in other cars but it only lasts for maybe 2-3 seconds. You press the throttle and nothing happens. Just bogs. Then she will finally accelerate.)
My local dealers tried a reset on the transmission Adaptive learning, a new Valve Body, got a hold of tech line to the answers was--- "its the way the driver is driving the vehicle"
Can somebody- anybody please help-
This is my 2nd ST- 1st one was a 2020 and it started to do it at the same kms- this is #2 a 2021 ST and its bad - i have only put Borla cat back exh. and H&R lowering springs on- tried a "Roar Pedal" it just makes the problem way more pronounced. Its pretty frustrating.

 

[Blue Beast]

Welcome to the forum.

 

[StevieB]

Hey y'all.

Been lurking the forum for a while now. 2020 ST owner with most of the upgrades y'all recommended. Whipped IC, JLT catch can. No aftermarket tune yet until I'm certain the tranny won't have an issue like some have been experiencing.

So far, I've had the weird clunking from somewhere under the truck. I think that is the gas tank issue. Some hard shifts but I'm an lead foot, so I figured it's my driving style.

However, last week I started having a new problem. At normal speeds, like taking off from a slow right turn or starting up after a stop in traffic, the throttle lags for a couple of seconds before it engages. Almost like limp home mode in other cars but it only lasts for maybe 2-3 seconds. You press the throttle and nothing happens. Just bogs. Then she will finally accelerate.

I've read through just about all the forum posts, but didn't find anything specific. A few mentions of power loss but not sure if that's a related problem.

Anyone else having that issue?
2020 ST, about 5k miles. No tune, just AM Whipple IC. I did double check all the hoses yesterday to make sure a clamp hadn't come loose. It's intermittent though. Always at Low speeds.

Hello there I have had a 2020 and traded it for a 2021 and they both did/ do it. I am currently working with a local guy on fixing it. He is using a HP tuner and he spent the better part of a day and we had to tweek a few more things. We found the fuel deceleration control mode was kicking in and shutting fuel off at any speed from 0-35 mph/ it will also do it on a higher speed situation as well. Once we get it I’ll let y’all know what the issue.

 

[Suprawill1]

Hello there I have had a 2020 and traded it for a 2021 and they both did/ do it. I am currently working with a local guy on fixing it. He is using a HP tuner and he spent the better part of a day and we had to tweek a few more things. We found the fuel deceleration control mode was kicking in and shutting fuel off at any speed from 0-35 mph/ it will also do it on a higher speed situation as well. Once we get it I’ll let y’all know what the issue.

Be curious to know!

 

[StevieB]

Be curious to know!

Are you having the same issue?
I have talked to many ST owners and even a Platinum owner when I meet / come across them and ask and they all say they do have the same issue. But didn’t recognize it as a problem. Which I find as weird! However to each is own.

 

[Excalibur]

When you mention gas tank issue, what exactly are you talking about? Just curious as I also have a noise from below in the rear. I can't tell if it's just the diff brace, sway brackets, or maybe something you're referring to. Mine is prominent when applying brakes at slow speed and weight transfers.

 

[Suprawill1]

Are you having the same issue?
I have talked to many ST owners and even a Platinum owner when I meet / come across them and ask and they all say they do have the same issue. But didn’t recognize it as a problem. Which I find as weird! However to each is own.

I don't really claim the same issue but I did once notice throttle lag a few days ago. Hadn't had before then or since. Maybe it was just a high gear bog down.
If it were persistent, I would surely consider it a problem.

 

[StevieB]

Does anyone have any Datta logging for the normal mode in a HP Tuner? We have found that when you step on the throttle - take away press as if to slow down and then to get back into it to speed up that the throttle body plate shuts the fuel off completely. ‍♂️ any help would be awesome.

 

[Cruising68]

Does anyone have any Datta logging for the normal mode in a HP Tuner? We have found that when you step on the throttle - take away press as if to slow down and then to get back into it to speed up that the throttle body plate shuts the fuel off completely. ‍ any help would be awesome.

That’s certainly what it feels like. I am out of town for a bit but I can try and catch it during a logging session when I get back late this week.


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[bPRIME999]

I've had the same issue for almost as long as I've owned my 2020, but have never been able to have it diagnosed by my Ford dealer or a private mechanic.

When I leave my house, the first right turn I make always throttle lags for a few seconds, and if I press down more, it does nothing, it just jumps harder when it eventually kicks back in. It's very annoying and honestly quite scary as it happened one time when I was crossing the highway (driving straight, not turning) and that few seconds felt like an eternity with traffic coming from either side...

Very curious to see what you come up with!

 

[Cruising68]

Thanks for the reminder, I completely forgot


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[Suprawill1]

I experienced this for the first time yesterday in the 2020. I was in normal mode and cruising along when I needed full throttle. I pretty much slammed the accelerator down and nothing for apprx 2 seconds and then it did what it was initially supposed to do. Disheartening for sure.
Would be interesting to nail this down. Getting ready to go out now and I'll try the same thing but in sport mode to see if there's a difference.

 

[Dennis]

I have both problems and for me these are separate issues when changing lanes quickly and acceleration at speed and starting a right turn with a bit of gas.

I solve the right turn with gas by turning off the traction control. No need to go full accu-trak press and hold, just turning off the traction let's it gas nice and brisk from a stopped right turn.

The changing lanes at speed and attempting to accelerate has been covered in another thread and I believe people think its some programming downshift/quick steering movement issue.

Dennis.





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[bPRIME999]

Suprawill1, I experience the throttle lag in either sport or normal, doesn't seem to matter. I imagine yours would be the same, but curious to hear.

Dennis, I habitually turn traction control off and still have the issue myself, but thay right turn I make is more of a yield then a full stop, and I wonder if that's the difference? That said, it doesn't occur for me exclusively on right turns either.

 

[18Ventura]

I have experienced this as well. My theory is this has something to do with collision avoidance. If you accelerate quickly, then completely/significantly back off the pedal, particularly while turning, the throttle sometimes cuts out momentarily. And comes right back after a brief hesitation. I think the car thinks you're trying to avoid hitting something, and is anticipating that you're about to slam on the breaks. I have found the issue to occur less frequently with the traction control off. (Not full off.)

There are a couple of funky corners that I drive regularly. Depending on how I drive, I can virtually duplicate the bog-down on command. I've also figured out, however, that as long as I don't back off the throttle too much, I can avoid the problem altogether. Just powers right through those same turns.

I believe it's the sudden lack of throttle that tricks the ST into momentary panic mode.

Of course, my theory could be complete BS. But that's all I have to offer.