I have a 2005 2.5L Z4 automatic. It seems to me there is a slight
hesitation when I start from a complete stop. Then it takes off. Not
smooth at all.
This is in contrast to my Toyota truck (stick) which does not hesitate at
Also, I was messing with the S/R and clock buttons when the odometer changed
from miles driven to number 6. I managed to increase the number to 8 before
it went back to mileage. Anybody else ever done this?
I was unaware of it until you brought it up but it is a SMG transmission.
I can either put it in drive or pull the shifter towards me. I tap it up to
increase the gear or tap it down to down shift. I normally drive it, and
the reason for the post, in drive and do not change gears manually.
Thanks for the help. Now I am going to research it to see if I can adjust
it to help eliminate the hesitation.
On Thu, 27 Dec 2007 12:12:09 -0800, " email@example.com"
I'm in the rare position of having driven all the BMW SMG transmission
offerings (thanks BMW Performance Center!) and they all exhibit the
hessitation. As you prbably know the SMG is really a manual
transmission with an automated clutch. I think the delay is just the
combination of the ECU having to see your foot release the brake and
apply throttle input so it knows you want to move forward. That
decision making process plus the actual movement of the clutch takes a
fraction of a second and you can feel it. I'm not aware of any
improvments that BMW can offer (but do check it out). You might want
to investigate the aftermarket (ie. www.dinanbmw.com) as some of them
might have an improvemnt to the software. Dinan modificatiosn do not
void your warranty.
I took it to Dinan and it turns out to be a steptronic transmission and not
SMG. However they said the same hesitation is found in both. One tech said
he noticed it in his 325 and upgraded the software which seemed to help the
response. The software is $299 with an hour of upload. Bad news is the
software is 49 state legal (not California) but they are trying to get it
accepted in California. I will probably purchase when it is accepted or BMW
provides an upgrade.
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