545 Hesitation from the stop
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Joined: Apr 2004
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For the record . . . when the vehicle is stopped and idling the automatic transmission is in second gear. The hesitation you experience when pressing the accelerator is the transmission downshifting to first gear before pulling away. Whether in D or DS mode, the transmission will operate in this manner. Downshifting to M1 while in DS mode will eliminate the hesitation, although manual intervention at every stop is unsatisfactory for most of us.
All versions of the E39 automatic transmission (Steptronic, non-Steptronic, 4-speed, and 5-speed) did this as well. The difference is that the E39's downshift operation from idle was much quicker and nearly imperceivable. The E60's downshift operation from idle is slow and noticable. Adjusting the idle may help to mask the hesitation, but the problem remains. The issue exists within the ZF 6-speed or the transmission programming. Perhaps someday we will know the exact cause.
All versions of the E39 automatic transmission (Steptronic, non-Steptronic, 4-speed, and 5-speed) did this as well. The difference is that the E39's downshift operation from idle was much quicker and nearly imperceivable. The E60's downshift operation from idle is slow and noticable. Adjusting the idle may help to mask the hesitation, but the problem remains. The issue exists within the ZF 6-speed or the transmission programming. Perhaps someday we will know the exact cause.
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Joined: Apr 2004
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From: Alabama, USA
So, dba1t, spirited acceleration from a standstill invokes a downshift to 1 while a regular take-off starts in 2nd with shifter in D? We do not get 6 gears while in D ever? 
And, in addition, the other comment, that in DS you get no 6th? Is the gear not accessed yet just displaying 6th? I thought I saw 6.
Now can anybody answer my outstanding question from months ago; is there a torque converter lock-up in this transmission? I can't feel it engage. <_<
And, in addition, the other comment, that in DS you get no 6th? Is the gear not accessed yet just displaying 6th? I thought I saw 6.
Now can anybody answer my outstanding question from months ago; is there a torque converter lock-up in this transmission? I can't feel it engage. <_<
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Joined: May 2004
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From: Frederick Maryland
Originally Posted by sg530' date='Dec 3 2004, 07:47 AM
And, in addition, the other comment, that in DS you get no 6th? Is the gear not accessed yet just displaying 6th? I thought I saw 6.?
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From: Schweinfurt, Germany
Originally Posted by ULtraPLanet' date='Dec 3 2004, 01:31 PM
[quote name='sg530' date='Dec 3 2004, 07:47 AM']And, in addition, the other comment, that in DS you get no 6th? Is the gear not accessed yet just displaying 6th? I thought I saw 6.?
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[/quote]I used M mode today for the first time (finally out of the break-in mode after the meet) I shifted back and forth a couple of times. I left it in M3 forgetting about it for a moment when my wife called on the cellphone. The traffic light changed, I started up looked down at the instruments and noticed it was still in M3. Did it start in 3rd?
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Joined: Mar 2004
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From: New Orleans, LA USA
My Ride: E90 M3
Model Year: 2011
Originally Posted by gomac' date='Dec 3 2004, 12:12 PM
[quote name='ULtraPLanet' date='Dec 3 2004, 01:31 PM'][quote name='sg530' date='Dec 3 2004, 07:47 AM']And, in addition, the other comment, that in DS you get no 6th? Is the gear not accessed yet just displaying 6th? I thought I saw 6.?
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[/quote]I used M mode today for the first time (finally out of the break-in mode after the meet) I shifted back and forth a couple of times. I left it in M3 forgetting about it for a moment when my wife called on the cellphone. The traffic light changed, I started up looked down at the instruments and noticed it was still in M3. Did it start in 3rd?
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[/quote]It probably did. I've never done that one. I think the computer will step in and stop you from doing something that will harm the engine, like downshifting from 5th to 1st, starting in 3rd, while a bit sluggish maybe, is probably not very harmful to the engine or transmission.
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Joined: Aug 2004
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From: Minneapolis, MN USA
My Ride: 2004 545iA Titanium Silver/Gray, Poplar----Cold Weather Pkg, Comfort Seats, Logic 7 Audio, Heated Rear Seats
Originally Posted by gomac' date='Dec 3 2004, 12:12 PM
I used M mode today for the first time (finally out of the break-in mode after the meet) I shifted back and forth a couple of times. I left it in M3 forgetting about it for a moment when my wife called on the cellphone. The traffic light changed, I started up looked down at the instruments and noticed it was still in M3. Did it start in 3rd?
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[/quote]
I used M mode today for the first time (finally out of the break-in mode after the meet) I shifted back and forth a couple of times. I left it in M3 forgetting about it for a moment when my wife called on the cellphone. The traffic light changed, I started up looked down at the instruments and noticed it was still in M3. Did it start in 3rd?
I do mostly city driving and whiile in M if I shift to 4th, it will automaticly shift back to 3rd if my speed is not great enough to keep the revs above 1K.
In a 545 I have started from 3rd and the car takes off a little more smoothly, although more slowly till it hits the strong part of the tourq curve. I don't know if a 530 would have enough torque to pull this off.
I think the delay is caused by the lack of pressure in the torque converter. It takes an instant to build pressure before acceleation is felt. This is why @ 750 the hesitation is not a notible because the higher RPM is creating more pressure. Too much pressure at idel and the car would tug when at a stop, but there would be no delay.
I used M mode today for the first time (finally out of the break-in mode after the meet) I shifted back and forth a couple of times. I left it in M3 forgetting about it for a moment when my wife called on the cellphone. The traffic light changed, I started up looked down at the instruments and noticed it was still in M3. Did it start in 3rd?
[snapback]64025[/snapback]
[/quote]I do mostly city driving and whiile in M if I shift to 4th, it will automaticly shift back to 3rd if my speed is not great enough to keep the revs above 1K.
In a 545 I have started from 3rd and the car takes off a little more smoothly, although more slowly till it hits the strong part of the tourq curve. I don't know if a 530 would have enough torque to pull this off.
I think the delay is caused by the lack of pressure in the torque converter. It takes an instant to build pressure before acceleation is felt. This is why @ 750 the hesitation is not a notible because the higher RPM is creating more pressure. Too much pressure at idel and the car would tug when at a stop, but there would be no delay.
