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Slow Acceleration on highway

plehrack

Member
Mar 27, 2020
17
8
Los Angeles, CA 91356
I recently went on my first extended road trip in some time and found that autopilot was accelerating very slowly during traffic speed ebbs and flows. When traffic slowed, autopilot slowed appropriately behind the lead car. Once the lead car accelerated, autopilot very slowly increased speed which allowed the lead car to get several hundred feet out in front of my car. This caused much angst for the drivers behind me who started flashing their headlights followed by changing lanes and flying past me.

This must be a reletively new behavior as I didn't notice it a few months ago. Has anyone else had this issue? Is there a solution? Reboot the car? Changing the follow distance does not improve this behavior.

What think?

Peter Lehrack
Tesla Model S Performance Raven Edition
Software v 2021.24.5
 

GtiMart

Active Member
Nov 13, 2019
1,406
1,230
Quebec City, Canada
If people in front accelerate quickly, I also find the car doesn't follow quickly enough. And in general I find the deceleration correct. I'Ve seen many people that find the deceleration too harsh, and probably acceleration too rough as well. They can't please everyone I guess. Maybe we need a "mad max" setting for TACC/Autopilot as well.
You can leave Autopilot on and push the accelerator. That's what I do sometimes to accelerate faster. Once you let go of the accelerator, TACC/Autopilot will resume.
 
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bpnine

Member
Apr 17, 2021
6
2
MSP
I've noticed (2021MY) that its a bit more crisp accelerating in freeway traffic if I set the follow distance to 1 (though I don't really like tailgating despite the energy benefit). It would be nice if there were advanced settings somewhere you could access that would let you tune some of these parameters (curves for braking, accelerating, and lateral acceleration during lane changes, how much to slow down around curves at various speeds, etc), though I suppose the risk is its hard to test with so many configurable dimensions.
 
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bpnine

Member
Apr 17, 2021
6
2
MSP
Oh, I've also noticed more recently (last couple of releases) that it seems to start *very* slowly from a red light, I always have to goose the accelerator if there are folks behind me because its so lethargic.
 

plehrack

Member
Mar 27, 2020
17
8
Los Angeles, CA 91356
I'll try forcing a restart of my car... Grandma's Prius leaving one of the fastest accelerating production cars in the world in her dust seems very wrong. It did not used to be this way. Having to press the accelerator every time traffic speed increases is a big minus as far as quaility of experience using autopilot is concerned.
 
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EVRider-FL

Member
Aug 18, 2015
812
458
South Florida
Slow acceleration in TACC/Autosteer isn't a new issue, I've experienced that many times over the years. It doesn't happen all the time, and maybe it happens more now than it used to (I'll know after my upcoming road trip). Just tap the accelerator.
 
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HookBill

Member
Dec 28, 2015
652
689
The OC, CA
Oh, I've also noticed more recently (last couple of releases) that it seems to start *very* slowly from a red light, I always have to goose the accelerator if there are folks behind me because its so lethargic.
I am experiencing the same problem from both traffic lights/stop signs as well as in stop and go freeway traffic. Very frustrating to say the least considering everything was working fine until this update.
 

techlogik

Closed
Mar 22, 2021
380
271
FL
Nothing new. My 3 month old vision only has done this since day 1. I find myself many times just disengaging the AP and drive by hand so others behind me aren’t infuriated with the stupid slow acceleration and giant gap it leaves. Then the opposite happens when slowing it will ram on the brakes abruptly and dangerously due to the crap vision system having terrible depth perception apparently when coming to a stop in traffic. Beta shows all sorts of smooth stopping and slowing. But that applies to like 5 people with FSD Beta. Regular FSD does the same thing on all cars. Even sometime on 5-6 setting it does this, can’t even put it on 2. Still follows too far behind then the stopping issues. It’s a mess.

The list of massive fails goes on and on. Swerving through an intersection every time when there is nobody next to you, like you are in the right lane of a 3 lane road and although the lines on the screen show normal lanes (imaginary of course) it thinks are there that aren’t real, but the projected path, the stupid cameras must see and think it needs to move to the right briefly to center itself in the intersection. Unnerving again and dangerous stuff. Don’t even have time to type all the other stupid things this car does on 4.21.3. Tip of the iceberg.
 

Routybouty

Member
Nov 22, 2015
91
89
Fort Wayne, Indiana
It's most likely software version related. It seems they gimp acceleration every few software updates and then ungimp it a few later. At least that's my experience over the past 2.5 years. Right now, it's gimped and annoying.

A new behavior as of this (24.10) or the previous release is the inability to hold constant follow distance. During a recent 300 mile trip a follow distance of 1 would hold about 1-1.5 seconds behind the lead vehicle. During any elevation increase, that would change to about 6-7 seconds behind, slowing way below max set speed, before the car figured this out and then promptly speed back up to the lead vehicle.
 
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plehrack

Member
Mar 27, 2020
17
8
Los Angeles, CA 91356
I’m currently on a road trip and NOA is almost unusable. For example, it was forcing me to use the carpool lane to follow the route but that lane was not required to stay on the route and was much slower than the #1 lane. It kept turning the blinker on, then I would cancel. Over and over and over and over and just forget it. NOA off.

I’m driving in the San Diego area and it took 2 bad exchange which caused reroutes. It also made last second lane changes which were outright dangerous.

When a lane expands and one line isn’t yet visible, instead of using the lane line that has been stable for the past few seconds as a guide, it tries to center on the open area then swerves back suddenly once the new lane line is visible. This too is dangerous.

I’m guessing that Elon or anyone else from QA haven’t road tripped the latest build or people would be fired.
 

WattsappMTL

Member
Nov 2, 2020
153
93
Montreal
Fully agree that following distance increases too much with the recent software releases. I do like that it's more subtle in acquiring (and maintaining) the following distance when you're approaching another vehicle - or if one cuts into my lane - but the lag in accelerating is annoying. Pressing the accelerator is a solution, but from my experience with automation in the aviation world, mixing manual and automated control is not recommended because it have safety consequences. I've already noticed this when I use Autosteer together with a lot of lane changes - sometimes I forget that I didn't re-engage and wonder why the car is drifting toward the side of the lane because I'm not actively steering. For that reason, I feel Tesla should have included lane change on signal as part of basic Autopilot instead of only offering it with Enhanced AP or FSD.
 

EVEnergy

Member
Sep 2, 2021
24
20
Wyoming
I’m currently on a road trip and NOA is almost unusable. For example, it was forcing me to use the carpool lane to follow the route but that lane was not required to stay on the route and was much slower than the #1 lane. It kept turning the blinker on, then I would cancel. Over and over and over and over and just forget it. NOA off.

I’m driving in the San Diego area and it took 2 bad exchange which caused reroutes. It also made last second lane changes which were outright dangerous.

When a lane expands and one line isn’t yet visible, instead of using the lane line that has been stable for the past few seconds as a guide, it tries to center on the open area then swerves back suddenly once the new lane line is visible. This too is dangerous.

I’m guessing that Elon or anyone else from QA haven’t road tripped the latest build or people would be fired.
The solution for me was to turn on the lane change confirm (by using the blinker) - the car will show me it wants to change lanes but I can either ignore it or start the signaling process and it works without annoying other drivers or giving false signals.

It's always done the land widening thing; I'm pretty sure it knows what's coming up and I don't know why it doesn't react to it. It might be the "4D" that Elon was talking about which should be coming in the coming updates.
 

Wingsy

Member
Apr 30, 2019
161
223
Mocksville, NC
I recently went on my first extended road trip in some time and found that autopilot was accelerating very slowly during traffic speed ebbs and flows. When traffic slowed, autopilot slowed appropriately behind the lead car. Once the lead car accelerated, autopilot very slowly increased speed which allowed the lead car to get several hundred feet out in front of my car. This caused much angst for the drivers behind me who started flashing their headlights followed by changing lanes and flying past me.

This must be a reletively new behavior as I didn't notice it a few months ago. Has anyone else had this issue? Is there a solution? Reboot the car? Changing the follow distance does not improve this behavior.

What think?

Peter Lehrack
Tesla Model S Performance Raven Edition
Software v 2021.24.5
I think most people have this same problem, me included. The thing that gets me is when coming up on a car in your lane that is say, 5 mph slower than you, it will run right up to his bumper (maybe 3 car lengths) while decelerating rapidly, then slowly back off to the set following distance, more or less. Why doesn't it target the set following distance as the point where it should ultimately be, rather than to get too close followed by gradually finding the right spot?
 

mark95476

Active Member
Jun 21, 2020
1,846
1,427
Bay Area CA
Anyone that's complaining about slow acceleration isn't used to being a passenger. The Tesla is a super fun car to drive, but it'll make passengers motion sick with hard acceleration/braking and go-kart handling. AP is doing what it should be doing with gradual almost imperceptible acceleration.

I love going ~70, flooring it, and blasting by slower traffic when driving by myself. It's the complete opposite when I'm a passenger.

Slow acceleration in TACC/Autosteer isn't a new issue, I've experienced that many times over the years. It doesn't happen all the time, and maybe it happens more now than it used to (I'll know after my upcoming road trip). Just tap the accelerator.
 

mark95476

Active Member
Jun 21, 2020
1,846
1,427
Bay Area CA
"Just tap the accelerator."

What did you do when you didn't have AP?

It's like getting to a green traffic light. Tap to proceed. In this case, tap to accelerate quickly if someone's behind you.

And infuriate most of the drivers behind you. I don't want that in my Tesla.
 

pault72

Member
Apr 19, 2017
22
2
Minneapolis, MN
I also recently noticed the slow accelerating in stop and go traffic with the AP. It wasn't like this before. This is new. When the traffic slows or stops and the car in front starts to accelerate, Tesla doesn't accelerate to keep up with the car in front (by at least 2-3 car lengths). It's so bad that people behind honk or other people merge in front of me. Makes AP unusable. Very frustrating!!! This I believe is a software issue because my wife's 2021 MY does it as well as my 2020 MS Performance. MY has vision only and MS has vision and radar. Hopefully they get it fixed soon! Makes the $10k in Full self-driving a waste.
 

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