[sard]

Whatever term is used .. I'm referring to accelerating from a dead stop as was well described by www.edmunds.com

"The X3 is frustrating in low-speed stoplight driving, however. The throttle requires a very committed input before the engine delivers power, as if the turbo six were awaiting approval from an electronic committee before finally whipping the horses into action. The hesitation goes beyond mere turbo lag, and makes for jumpy, uneven driving around town. It's not notably better in Sport mode, either.

Perhaps this is the cost of fuel economy, but we're still not fans."

I definitely noticed this immediately when test driving the X3 35i. I've seen one other post about this on this forum, but it still has me worried.

Does it improve over time? Do you just get used to it and then it's not an issue? Does it still annoy you? Thanks in advance.

[paul386]

I have a 35i and I don't notice this problem in any mode (regular / sport). The only thing I notice is that when at low speeds the car feels like it has a lot of "drag" on it when you lift.

Granted the throttle response is generally poor in regular mode but this is due to throttle damping for fuel efficiency that will be found on most all cars.

[Radioactive]

I know this issue has been addressed in early threads, but it’s been one of those days and the lag happened again today, so I feel compelled to comment. I was previously in the camp of “you learn to adapt to the car”. But now I’m not. I grew up in the car culture of SoCal and in over 40 years of driving cars from Porsches to Tractor Trailers and everything in between; I find the throttle response to be the worst of any car I’ve driven. I find this car difficult to drive smoothly. To me, it’s the inconsistently of the response. Sometimes it’s no problem, other times you keep pushing and pushing. The worst for me has been, including today, is going uphill, pushing on the accelerator and no response. I have about 3K miles on a 28i and things are still the same, although the SP mode is better. I love the car, but this bugs the sh*t out of me so badly that if there was another car that fit my needs/wants as well as the X3 I would take a hard look at it.

[sard]

That's discouraging. I guess when my car finally arrives, I'll test drive it and see how bad it is. Might decide not to take it.

[colton_matthias]

Are you guys referring to the unsmooth take off especially at stop signs without a complete stop?? If so this is VERY annoying.

[XB101]

Argh, that is not good to hear.

[sard]

No, the non-linear acceleration from a dead stop. At a dead stop, when you initially press the gas pedal the car doesn't move. You keep pressing down and then you'll finally reach the point where the car is programmed to start accelerating, but it's somewhat of an abrupt and not smooth rush forward.

[sard]

A lot of posts say the delay is improved with sport mode. Does a M Sport optioned X3 without Dynamic Handling Package have a sport mode?

[DJ Daddy-O]

There is a post in the 5 series forum about this and it includes a step plan to reset the transmission program. If this is the same issue then many have reported that these actions have fixed the delay issue.

I am on my iPhone so not sure I can post a link but perhaps someone on a proper computer can hunt it down.

Ps just browsing the 5 series forum out of interest I am not considering defecting!

[BMWZ4]

You could try this bit of tech:

http://www.sprintboostersales.com

I used this on an '06 MX5, worked great & solved a similar type of accelaration lag. Not sure if they have it for the F25 though, guess you could contact them to find out.

Dave

[colton_matthias]

Originally Posted by sard

No, the non-linear acceleration from a dead stop. At a dead stop, when you initially press the gas pedal the car doesn't move. You keep pressing down and then you'll finally reach the point where the car is programmed to start accelerating, but it's somewhat of an abrupt and not smooth rush forward.

Not really then...

[mibmwx3]

Sard, Mine acts the same way as the one you tested and it does annoy me. It's improved in sport mode, but still there. Hasn't improved in 2000 miles.

[Le Chef]

Did BMW intentionally make it this way, or is it a flaw? Can the throttle and gearbox software "unlearn" this or is it permanent in Normal? Does it apply equally to both 28 and 35 or is it specific to one and not the other?

[TN_3]

Here is the thread on 5post.com detailing the procedure to reset the transmission...

http://f10.5post.com/forums/showthread.php?t=455949

Also, reading through that thread, one forum member mentions that BMW is aware of the transmission lag issue (at least on the F10) and is working on a software fix.

[colton_matthias]

Originally Posted by TN_3

Here is the thread on 5post.com detailing the procedure to reset the transmission...

http://f10.5post.com/forums/showthread.php?t=455949

But its only a temporary fix... is there anyway to permanently make the car learn the throttle (with very aggressive driving with the throttle for example)?

[Harplayr]

I have a 28i without any sport option.
I haven’t noticed any lurching on my car.
It starts smooth from both dead stops and rolling stops under soft acceleration and hard acceleration.

[Nahoa]

35i + Sport version of Harplayr.

I can make it lurch if I don't pay attention to how I'm driving. No indication what so ever of any lag -- unless my foot's too slow.

[Beyu]

I find that the X3 only "lurches" when trying to accelerate hard after a complete stop and have not experienced any lag that you guys speak of. Another member mentioned something about throttle damping, perhaps someone can explain this in layman's terms. I've also experienced something similar to this in two previous Mercedes so perhaps Paul386's right and BMW and other car companies are purposely doing this and is not an inherent flaw in the X3's design.

[MikeBimmer]

Mine does a similar thing(2.8, non-spt). Very lurchy/crazy surging, especially when cold. Seems like I need to rev it at idle to keep it from stalling/stumbling when cold. Tip-in seems very weak but builds steadily at about half throttle. Warm the motor seems happy but accel is sluggish.

[paul386]

Originally Posted by Beyu

I find that the X3 only "lurches" when trying to accelerate hard after a complete stop and have not experienced any lag that you guys speak of. Another member mentioned something about throttle damping, perhaps someone can explain this in layman's terms. I've also experienced something similar to this in two previous Mercedes so perhaps Paul386's right and BMW and other car companies are purposely doing this and is not an inherent flaw in the X3's design.

Throttle damping is software "filtering" of your throttle to make your throttle inputs seem more smooth. It is intended to prevent throttle spikes that would reduce fuel efficiency. To the driver it feels like a lag.

[MikeBimmer]

[QUOTE=MikeBimmer;10038836]Mine does a similar thing(2.8, non-spt). Very lurchy/crazy surging, especially when cold. Seems like I need to rev it at idle to keep it from stalling/stumbling when cold. Tip-in seems very weak but builds steadily at about half throttle. Warm, the motor seems happy but accel is still ratchety

[Nahoa]

Still not experiencing what y'all are. Took a drive in the "mountains" (more like hills) today. Some decent grades and this thing climbed like a champ. Hardly noticed the climb. Blew past lugging cars doing 70, having to hold back from going faster. Engine only slightly different than level ground. "Stump-pulling" torque is no joke. Climbs at lower speeds were similarly a breeze.