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      10-12-2012, 03:17 AM   #1
giorgioarmani
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automatic 1st and 2nd gear roughness

So the sportauto car is slowly rolling to a red light at 10 mph then 5mph etc, and just before the car is about to come to a full stop, the light turns green.

You step on the gas pedal to proceed, not flooring or anything, just enough to make a clean getaway. Here is where the jerk happens.

Rather than holding itself in 2nd gear, the tranny decides to shift to 1st. The driver, mentally still in 2nd gear since a full stop has not happened, presses the pedal and, snap, what would have been perfect throttle for a 2nd gear rolling restart now became a needlesly jerky over throtled 1st gear departure to 3500 hundered rpm sometimes

In sport mode this is fine. In comfort however, 1st gear could have been bypassed perhaps or programmed so the tranny doesnt drop to 1st unless the car has come to a complete stop. aminuts?
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      10-12-2012, 03:39 AM   #2
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I'll try this myself as you describe, but I know what you mean. Depending on the situation (requiring acceleration) by the amount/level pushing the gas pedal, the software decides to downshift, especially on lower revs. Think that's normal. Had similar phenomena in higher gears (4th to 2nd). I think this is inevitable with any auto feature. (There will always remain a difference between the way you think gearbox should react against how soft is programmed). However and depending on the power need, it should be logic not to downshift if minimal power needed. Like I said, I'll try this myself and post experience later on.
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      10-12-2012, 07:18 AM   #3
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To the OP. Your description is spot on.
It can become very irritating.This same old song happened many times when I had my F10 535i 8AT sport.

One of the mainreasons why I got back to a manual transmission tbh.

Cheers
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      10-12-2012, 08:58 AM   #4
giorgioarmani
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Quote:
Originally Posted by Robin_NL View Post
To the OP. Your description is spot on.
It can become very irritating.This same old song happened many times when I had my F10 535i 8AT sport.

One of the mainreasons why I got back to a manual transmission tbh.

Cheers
Robin
well im glad then im not the only one in this case and that im not mad. The issue is a very abrupt jolt that could be solved by the car not shifting into first. but hey, doesnt seem like there is much i can do about it.
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      10-12-2012, 09:04 AM   #5
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It'll eb as simple as the angle of the throttle pedal is greater than you think. You're reacting to a light going green and hitting the throttle. You'll just be hitting it hard enough for the software to think you want kick-down and it'll drop a cog.

I'm sure it's frustrating but I also think it's perfectly normal behaviour. Even a transmission as good as the 8AT can't read you mind and is only acting as the programmers designed it
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      10-12-2012, 09:38 AM   #6
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Quote:
Originally Posted by MaestroAl View Post
It'll eb as simple as the angle of the throttle pedal is greater than you think. You're reacting to a light going green and hitting the throttle. You'll just be hitting it hard enough for the software to think you want kick-down and it'll drop a cog.

I'm sure it's frustrating but I also think it's perfectly normal behaviour. Even a transmission as good as the 8AT can't read you mind and is only acting as the programmers designed it
I think this is a very good answer.
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      10-12-2012, 10:41 AM   #7
J1n
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Same here it's normal
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