Is anyone else experiencing following:

When stopped (i.e. traffic light) and when I take my foot off the brake and hit the gas right away the car seems to hesitate for a split second before it goes. This is only reproducable when I hit the gas immidiately after I take my foot off the brake pedal. It does not matter if step on the gas lightly or if I really get on it as long as I touch the gas immidiately after the brake. It hesitates every time.
If I wait for a second or two and then press on the gas everything is just fine.

What is going on here?

 

What trans do you have?

 

It is an automatic.

 

It is an automatic.
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this is the same pause I spoke about in an earlier thread. I too have the auto transmission.

 

There have been several threads about this and similar issues.

The latest thread was here:
http://forums.e60.net/index.php?showtopic=4866

I have the problem, too. I have not seen a definitive solution on any board, nor am I aware of a BMW bulletin, but it does not seem to be uncommon. Some have claimed that software updates have eliminated (or made worse) the problem. I haven't given my dealer a crack at it yet, but I will eventually. I was hoping for more specific information first.

What's your build date? Does it only occur at certain idle RPM (500)? Does it occur when you have the Steptronic set to DS mode?

My hesitation occurs only when idling at 500 RPM. It may not occur when in DS mode.

 

Tim, I have also been quietly tracking this issue, waiting for a solution, though there doesn't seem to be one just yet. Mine seems to happen in D but much less so in DS (if at all really). As for the RPM, I have the AC on all the time, so I'm always at 750 RPM or so when idling. Still happens at 750 rpm. I can't tell if it is a software issue or what. I do remember a thread (could have been on a different board, won't name it! ) about someone with a similar complaint where the dealer resolved it by tweaking up the cars idle RPM. It's never bothered me enough to bring in to the shop and given the mixed results of software updates, I want to avoid that as long as possible since other that the CD restarting on track 1, I have no issues.

 

I have no other problems, so I hear you on the software update. A, I don't want new problems, and B, I'm not convinced that is the solution. Raising idle speed does not appeal to me either, because I'm concerned that would raise the idle too high when the AC compressor is running and the idle is normally around 750 RPM. I do not believe I have the problem when the engine is idling at 750, though. I'm surprised you never see a 500 RPM idle because I think the compressor automatically cycles off and on, and even in New Orleans, it must be cool enough by now to take brief rests. I would like to know what the spec is for correct idle speed.

 

I have no other problems, so I hear you on the software update. A, I don't want new problems, and B, I'm not convinced that is the solution. Raising idle speed does not appeal to me either, because I'm concerned that would raise the idle too high when the AC compressor is running and the idle is normally around 750 RPM. I do not believe I have the problem when the engine is idling at 750, though. I'm surprised you never see a 500 RPM idle because I think the compressor automatically cycles off and on, and even in New Orleans, it must be cool enough by now to take brief rests. I would like to know what the spec is for correct idle speed.
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I'll play with it an turn off the AC. I use the Auto function for the climate control, so when I turn the temp knob up for heat, the AC light stays on so I assume the compressor stays on. I recall reading that leaving the AC on like this helps control the humidty. Anyway, who knows. I agree on the correct idle RPM, but I think around 750 w/ AC on and around 500 AC off is correct. And the other thread was a relatively small bump, so that no AC the car idled around 600 PRM, so we're not talking about a large increase.

 

I almost always run in the Auto climate control setting, too, but my warm idle varied between 500 and 750 RPM during hot days. It seemed to be dependent upon the AC compressor, but there may be other variables. The indicator lights do not reflect whether or not the compressor is running when you have the AC on.

I do not think that the car is idling too low at 500 RPM, causing the stumble or hesitation, but it is coincidental to the problem in my car. Considering the accelerator is electronic, the problem is almost certainly software. But where?

 

I have a question for you guys. I don't own an E60 yet so I wouldn't know, but why not just keep the car in DS mode all the time instead of reverting back to D Mode? I am assuming the reason is for better gas mileage?