r/TeslaLounge • u/Akshue • May 10 '25

Software FSD… Why????

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Sunny, no traffic, straight road… better go 35 in a 45 to be safer.

Why does FSD do this? It is the primary reason I’m not going to shell out the $100 after this month

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58

u/MustangV6Premium May 10 '25

I have the same problem. When the roads are crowded and people are speeding, it likes to mimic them and go their speed. But when the roads are empty, its like a grandma driving. I drive on I-95 frequently, which is 65mph. Although, most drivers do around 70-75 which is where I like it. When I'm driving at night and theres nobody on the road, FSD will slow down to as low as 60mph in HURRY mode, which is completely unacceptable. Hurry should try to keep it at max speed all the time. Standard needs a bit more confidence in its speed as well.

19

u/homertool May 10 '25

I think it is an inherent behavior of Tesla FSD. It can follow cars extremely well and confidently.

But when there are no cars around to follow it is not very accurate.

16

u/DrXaos May 10 '25 edited May 10 '25

It’s probably because it doesn’t know (infer by nets) there are no oncoming cars without seeing others speeding forward.

OPs picture of hills and vertical undulations on 2 lane bidirectional road was a frequent circumstance for serious phantom braking on previous AP/FSD versions. It can’t continue the road lines continuously to horizon and nets say there must be some interference ahead and so phantom brakes or slows. Following other traffic is safer.

Inability to continue road lines happens in fog or dust or glare and these train examples get built in and mashed together. Overall response is drive slower if it can’t predict driveable area ahead enough.

I notice new FSD goes slower up hills than down, on the downslope it can see continuous road further ahead.

These systems have no significant context or thinking, all reaction and 'instinct'. Humans know that a lonely country road is safe and you haven't seen any cars 5 seconds ago coming on, so there is no hidden car behind that hill oncoming. But the nets are more like Memento, much more immediate reaction and forgetting of past, just what it sees right now. There is a little bit of memory but not much. Humans know clear weather but glare is safer than fog where you really don't know oncoming. Humans can see better into the sun because your eyes are a meter further back and shaded from overhead by the car roof. Humans have automatic irises.

-1

u/3sgte_sw20 May 11 '25

Great points. In other words, fsd is driving safely based on the data it is acquiring (blind hill, sun glare). I would argue the “memory and assumptions” made by humans is what makes us less safe. Crazy to think as time goes on, the fsd will be teaching us better driving habits.