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TACC/Autopilot overreacts to cars changing lanes (not cutting-off)

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Scenario:
Model 3 LR/RWD. Freeway traffic, going full speed but comfortably stacked/spaced to each other. TACC set to 70, car doing 68, spacing set to "6".

A car in the lane to the right signals to change lanes, matches speed, and fits nicely into the "6" spaced gap between me and the next car.

Expected outcome: TACC would gently adapt to regain the space like a normal human being.

Actual outcome: TACC slams on the brakes, freaking out the traffic behind me, guy behind me moves to the next lane and is like "wtf", and regains the "6" spaced gap like nothing at all happened.

... Please tell me this is fixed for Version 9. :)
 
It's been my experience that if the car is going slower than me, it over reacts. If they are going faster than me and get in front it hardly reacts at all. Do you have your car set to normal or chill? Mine is set normal, but I've been thinking of setting it to chill while I'm in EAP/TACC mode.

My biggest issue with EAP/TACC is when a slower car decides to get out of my lane or exit the freeway, it acts like it's still in front of me and keep slowing me down. IE car going 65 taking the exit ramp starts slowing to 60, 55, etc... until I pass my car is matching their speed and they're no longer in my lane. I usually have to manually speed up until I pass.

As an aside: I use a "1" gap, considering how many cars can fit in the 1 gap I can't imagine using the 6, that'd be like a quarter mile between cars at freeway speeds. For reference, at 70mph using the "1" gap, a semi with a trailer can fit nicely between the car in front of me and myself, with room to spare. At lower speeds the "1" gap is much closer, but I'm rarely using EAP then.
 
I drive with a gap of 7, and rarely have these problems since the previous update a couple of weeks ago. Though it may be that the exact situation hasn't happened much, it feels like it has improved over the last month. It will slow down for slower cars, but nearly only really hammers the brakes when called for due to someone jumping in front at a fraction of my speed.
 
I drive with a gap of 3 and I do not see this. Although I have to say with a gap of 3, I get cut in very rarely and only usually during traffic and car would be moving around 30 mph instead of 70. I think I have about 5000+ miles on autopilot.
 
Comments here are interesting... a 1 gap leaving a semi-sized gap seems unusual. I usually had it set on 3-4 gap, but that's enough for a car to pop between me and the car in front. I wonder if there's something with the sensor calibration? I find my car has a seizure anytime I try to drive into my garage, and it screams at me to STOP! and provides distance estimates that are much smaller than the gaps that are actually there (ie I stop the car at "35cm" from the wall, but there's plenty of space more than that). Wonder if most other people have their cars super sensitive to proximity of objects, or if it's a sensor issue in my car... have enough issues that I'd not be surprised if this is another one I'm just learning about...
 
@Dante,
My car has major issues like yours when I go into my garage. I am honestly surprised at how much space my car leaves with a "1" gap while going 70mph on the freeway. But like I said, when going say 55mph, that gap is way smaller. So speed does factor into it.

All this said, I just got the 36.2 update Friday evening, so who knows? I may end up on someone's ass Monday on my way to work.
 
Well, to be fair, I don't see it as a sensor issue -- actually, I've also tried the TACC on the BMW i3 and the new LEAF, and they have the same problem - they overreact to merges and lane-changes pretty violently. It's like the car is completely unaware of the signaled actions of the other cars and just treat it like a collision risk.

Now, it doesn't happen every time, mind you. Usually if the lane-changing car is going at the same speed or above, TACC won't bat an eye, it'll do as I'd expect and gently regain spacing. But if there's a, hmm... a negative difference in relative speed and the merging car is vaguely approaching mine, it'll do the violent overreaction thing.

As for distance setting, I use "1" in two cases: in slow-moving/bumper-to-bumper traffic, or when at speed I want to shove my nose up the next guy's arse for going too slow. It's definitely "tailgating mode", but only really good to use at low speeds. Otherwise it's a pretty active signal that "dude it's 65 and you're doing 50". ;)

Parking distance sensors are 100% accurate except in close-cutting cases like at home, where I barely wedge the car between the gate and another car. It dings and bleeps bloody murder at me, sometimes even saying "stop!" but there's nothing behind the car - just very close to the sides. *shrug* Couldn't imagine that's the issue, though, as it perfectly judges curbs in parking spaces and walls behind the car. :)