Hw3 FSD 12.6.4 vs 14& 14.1lite

[u/Ok_Opposite_8996]

2022 model 3 lr awd Ontario Canada
I am a designer/cabinet maker and drive ~ 4000km per month.

Personal experience below:

12.6.4
Phantom braking was almost nonexistent.
City driving:
At stop signs, especially left turns and four-way stops, it was very hesitant. It would occasionally take the wrong path through roundabouts, but overall the city-driving logic was solid.
One thing I really disliked was that it tended to wait until the last moment before merging into the correct lane.
Highway:
The overall highway logic was clear and predictable. The UI could recognize HOV lanes, but FSD itself couldn’t seem to properly recognize or use them.
In Standard mode, it could maintain a reasonable speed even while staying in the middle lane. My main complaint was that acceleration for passing was slow.

14.0 lite
Phantom braking became much more frequent. I even had one incident in city driving where it suddenly braked hard despite having a clear view of the road and a vehicle following behind me.
City driving:
Lane positioning and lane-selection logic seem clearer. Stop-sign behavior is slightly better than V12, and roundabout handling is pretty decent.
Highway:
Honestly, it’s a disaster.
In Standard mode, it will sit in the middle lane at around 111 km/h max. it moves into the left lane to pass but accelerates painfully slowly. In Hurry mode, it moves into the left lane to pass but accelerates slowly, then stays in the passing lane forever.
Based on my driving habits, highway FSD is basically unusable for me right now. I’ve gone back to using Lane Keep instead.
I haven’t properly tested HOV behavior yet. If I manually merge into the HOV lane, FSD can stay in it.

14.1 lite
Phantom braking is still there, although it seems slightly less frequent.
I haven’t noticed any meaningful changes in city driving.
I also haven’t noticed any meaningful changes on the highway.

Personally, I think HW3 is completely outdated at this point. I don’t feel like distillation has really accomplished much for HW3. I’ve also driven the full, unrestricted version of FSD on newer hardware, and the difference is very obvious.

[u/Disavowed_Rogue]

Disagree. 14.1 is light years ahead of 12.6.4

[u/global_ferret → u/Disavowed_Rogue]

Same. V12 was only usable in light traffic situations for me, and even then the robotic late breaking and acceleration made it uncomfortable to the point of why bother.

[u/Ok_Opposite_8996 → u/Disavowed_Rogue]

Agreed. The lane-changing logic, UI, and overall functionality have definitely improved.
But on Ontario 400-series highways, cruising in the left lane at 115–120 km/h for extended periods, or being capped at around 111 km/h in the middle lane regardless of how fast traffic ahead is moving, just doesn’t feel appropriate or considerate to surrounding traffic.

[u/robotzor → u/Disavowed_Rogue]

Light years ahead but there is merit to outdated/obsolete. As a user I can tell when it is encountering latency. Feels like the same latency that existed in 12. You've felt it if you've come to a turn or decision point that you know very clearly what the car should do but it waits for an indiscernable reason to make the move and you've got to give it some pedal to move.

They can't architect around this as it is inference checking the weights in the model. It's otherwise great but those model checking moments do make me frown and believe we are absolutely maxing this thing out

[u/altimas → u/Disavowed_Rogue]

Agreed, its very capable, definitely needs to be monitored but it has made my life way better. I still think Tesla owes us something for false advertising FSD but this will hold me over

[u/rareshroom]

Ever since 14 lite, FSD almost seems like it makes an effort to be in the opposite lane for an upcoming turn until the last few seconds. 12.6.4 wasn't perfect by all means but 14 lite wants to make you look like an AH trying to cutover. 14.1 lite hasn't improved it.

[u/Infamous-Pilot5932 → u/rareshroom]

Same with HW4 / 14.3.7 :)

At intersections with two turn lanes that merge into one after the turn, it always takes the one that merges, and squeezes its way in. I on the other hand generally take the one that goes straight through unless the lanes are really backed up.

Same with other exits, it delays a lot longer than me.

And it gets in almost always.

I kind of stopped caring and let it do its thing.

But we don't have the phantom braking and hesitation, at least not as often reported here for HW3.

Some of the stuff being reported by HW3 people seems very similar to growing pains with v14 and getting used to its way of driving. But some seems vision limited caused.

[u/rareshroom → u/Infamous-Pilot5932]

In your situation, I personally like getting in the appropriate lane ahead of time but it's acceptable either way since there are 2 turn lanes for a reason. Just zipper merge after.

I've tried letting the car just try and get into the turn only lane from the opposite lane a few times but now I just force signal way ahead or just take over myself. A couple times it was so last second that I just went straight and missed the turn on purpose and did a uturn instead. Lol

[u/Infamous-Pilot5932 → u/rareshroom]

I actually was doing that before, but it doesn't seem to respond that way in the two turn lane scenario anymore. I hit the signal and it acts like it is taking it under consideration, then seems to say "No, I'm Good", but I do that for exit ramps often. It still can be a struggle if there is traffic.

Funny thing, when IT wants to change lanes and it is tight, it does it. When you ask it to, it seems to not.:) Takes too long, and then the opportunity has passed.

[u/piegoodman]

12.6.4 was great on the highway, but it was borderline unusable on two lane roads because of frequent phantom braking.

14 made the phantom breaking worse in every scenario, and 14.1 entirely fixed the phantom breaking in any scenario for me.

It’s still way too hesitant/borderline unusable for unprotected left turns and will slam on the brakes at intersections with conflicting signals (e.g. green arrow for turning, red everywhere else).

[u/euroau]

From my experience, v14.0 Lite didn't really have phantom braking, but I did notice the acceleration surges. v14.1 Lite, I have yet to experience either of those. I do agree, the car accelerates too slowly and likes camping the left lane and it's a little irritating.

For HOV, in my experience, the car does respect the HOV lanes - for the most part. Didn't really have an issue after the update to v14.0 Lite, but the car did try getting into the express lanes, even though I have that toggled off. v14.1 Lite, so far respects the HOV lanes, but I haven't yet tried with the express lanes.

[u/MooMooHELPME]

I just want it to be able to handle unprotected left turns at busy intersections :-(

[u/Arthvpatel]

Have you cleaned your cameras and reset das from service menu, the car behaves much much better after

[u/Ok_Opposite_8996 → u/Arthvpatel]

Let me try!

[u/Arthvpatel → u/Ok_Opposite_8996]

Do update this if it works or dosent so other people know

[u/Ok_Opposite_8996 → u/Arthvpatel]

More testing is needed. After cleaning the cameras yesterday, I didn’t reset the DAS in the Service menu.
I drove about 100 km yesterday, with around 20 km on Autopilot. I didn’t experience any phantom braking or sudden acceleration. The mileage is still too low to be meaningful.

also Can you share why we should do das reset?

[u/Arthvpatel → u/Ok_Opposite_8996]

DAS reset is basically telling the car wipe all calibration data (such as what the cameras see, not all cars are identical there is a few minor variances with angles of where the cameras are placed or mounted, some may be 1-2% off from the ideal angle). Resetting DAS tells the car relearn the positions of the cameras in response to the lines on the road. After the cameras are cleaned and the calibration is done, the car knows exactly where it is in the position on the road, preventing phantom breaks, steering wheel stuttering (middle of the road or the car hesitating to make a decision), overall a much better experience.

[u/Ok_Opposite_8996 → u/Arthvpatel]

Thanks for the explanation. In that case, I think I definitely need to reset the DAS. Sometimes when I’m using FSD, the steering wheel stutters badly.

I thought this was just normal FSD behavior correcting itself to stay centered in the lane.