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      01-29-2016, 05:23 PM   #1
Jetmart
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Hesitation

I did a search and found some had a slight hesitation however I don't believe it is what I am experiencing.

I have a 2011 35is with 7-Speed DCT. When driving around 60 km/h (30 mph) and steps on the accelerator to pass a car it hesitates a second or two before kicking down and taking off. Once it kicks down it takes off with full acceleration and downshifts appropriately. The engine is not sluggish and doesn't stumble. It is a hesitation in the downshifting process. It will do it in all 3 driving modes.

Any ideas?
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      01-30-2016, 08:17 AM   #2
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Is it tuned ?
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      01-30-2016, 09:21 AM   #3
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Is the car fully warmed up? I noticed it slightly but as I drive more and everything gets up to temp it seems to be fine...
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      01-30-2016, 10:43 AM   #4
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The car is tuned and fully warmed up to normal operating temps.
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      01-30-2016, 04:43 PM   #5
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Quote:
Originally Posted by Jetmart View Post
The car is tuned and fully warmed up to normal operating temps.
It is normal if it is tuned. Car does it when it is stock too, but you don't really realize that because you don't put down that much power, but when you tune it boost come little bit late. I even canceled the shift down button end of the pedal with tune.
What tune you have ?
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      01-30-2016, 05:38 PM   #6
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Quote:
Originally Posted by talhagursoy View Post
It is normal if it is tuned. Car does it when it is stock too, but you don't really realize that because you don't put down that much power, but when you tune it boost come little bit late. I even canceled the shift down button end of the pedal with tune.
What tune you have ?
I'm sorry I should have said the car is NOT tuned. I left out an important word.
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      01-31-2016, 04:38 PM   #7
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Same car, mine is a 2010. Mine does it all the time and they say it is normal. Just the DCT holding back the throttle while it is thinking what it wants and then letting the drive by wire throttle loose.
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      01-31-2016, 07:22 PM   #8
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I think you are correct. I have since been told the following:

1) DCT tech lines up the next required gear and is at its best accelerating through those gears. However, the downside is that it takes longer to choose gears that are not lined up. So as mentioned, choose the lowest gear you need manually before hitting the loud pedal.

2) Try using the paddles to downshift to your required gear...6th to 2nd is a long way to drop....

3) I think it maybe down to your expectation of the DCT. It is not a proper auto with a torque converter and I don't think the auto mode is as good as the ZF8 in that respect. You should pull the paddle to lower the gear, so you are in second, then overtake.
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      02-01-2016, 03:43 AM   #9
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Quote:
Originally Posted by Jetmart View Post
It is not a proper auto with a torque converter and I don't think the auto mode is as good as the ZF8 in that respect. You should pull the paddle to lower the gear, so you are in second, then overtake.
I agree. It is a matter of habits. I personally just flip it into S-mode before over-taking. It can be done very quickly, without looking down (oh, which paddle is now +/- etc), and makes all the difference.

I would say try not to use D + normal mode for sporty driving in general. It is probably bad for the clutches with all that slip between gears under power. Normal + M or DSC=off + M is perfect. No prolonged slipping and no clutch dumps either (like in S + Sport+), just perfect shifts.

Oh and BTW, when running in D-mode, the ZF8 is not better at downshifting quickly if you ask me. It is true that it reacts faster initially, but it has to stop over more gears on the way. The DCT just waits, picks a gear, adjusts the revs, and launches. It can pick 2nd although you are currently in 7th. The ZF8 has to do "touch-downs" on the way down from, say, 8th to 3rd, in order to protect the torque converter. So you will see the rpm counter moving in steps from low to high, whereas with the DCT it just goes "wrooom" in one smooth motion.

Also the DCT rev-matches on manual down shifts, and it sounds awesome. The ZF8 does none of that afaik. On the other hand, the ZF8 is much cheaper to replace, and abusing it is less of a concern (you can do launch control, burnouts etc without worrying too much).
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