Bimmer32

I have 2 probably simple questions:

1. In manual mode, is there a reve limiter? In other words, if I am in manual mode, and driving at 80 mph in m5, will the Steptronic tranny allow me to downshift to m2 (if by accident) or this there a safety feature? Has anyone every had their rpm needle go base the reve limiter? I'm assuming 6500 rpm.

2. I hear people say the Steptronic tranny "learns" your driving habit? What if I have a schizophrenic driving habit? How will it learn? Will it copy me and shift schizophrenically? I think it does.

Seriously, does anyone know "how" intelligient is this "learning" tranny? I'm a magnet for technical information.

znod

znod

Finally found it. Go here.

JayJay

I know that my standard auto box learns. I believe it stores the information on the key too. I find that at times if im in a sedate mood it will still hold it in gear a bit longer as though its saying 'go on you know you want too'.


A lot of the newer cars do. Dads 911 does the same thing. It annoys him that they reset it sometimes during a service because the car feels less 'agressive' when he gets its back.

Id imagine the M5 has the same thing.

znod

You could be right. I have never noticed the systematic effects you are talking about. I have noticed many what I would consider to be idiosyncratic/random effects. I wish good info on the 545i/Step was avaiable. I don't feel like I am able to find any good info on how things work. Did you check the link I posted out?

znod

I have more info on these issues now.

1. There is a rev limiter at least in manual mode. I have been able to demonstrate its existence under 20.01.00. I can hit the rev limiter by accelerating modestly while holding the Step in gear. I hit the rev limiter at about 6.7k RPM. I cannot hit it if accelerating at full throtte. Also, the Step will not let one downshift if doing so might hurt the driveline, engine, etc. And, protecting from bad downshifts is not the function of a rev limiter.

2. My car does learn. I demonstrated its learning ability to my satisfaction after updating to 20.01.00. At first, my subsequent performance was miserable. But, through frequent acceleration testing, my car relearned all, or at least most, of its original "fastness." My car is a slow learner. So, relearning took quite a while.

needforspeed

In manual mode, not only does my car not allow faulty gear changes (ie where it would be outside the rev range) is also changes up or down for me, without input.

For instance at say 35mph I will put it in m4 an it will change down to m3 - even though it runs perfectly well in m4.

I haven't used the steptronic all that much because this action sort of makes it - an automatic !

I've read the transmission pdf on the forum, but it only relates to the current engines. I have an M57 engine and (it appears) a different transmission as well.

Does anyone know if it works the same way?

znod

I don't know the engine numbers--even my own. But, if in manual mode, then the Step will do some shifting that you may not want unless you hold it in gear. You can, for example, hold M1 by keeping the lever pushed forward, but, even then, the Step sometimes will shift for you if it "decides that you don't know what you are doing"--i.e., you are cruising along continuously at an RPM the Step doesn't like for one reason or another. The bottom line is that the Step is not very accomodating to those who want pretty much control over RPM/gear combinations. For example, at full throttle, on cannot get the Step to shift manually at least once above 5k or so RPM--at least under 20.01.00 on my car.

needforspeed

Daft question - but if the step doesn't give you control and changes up or down as it sees fit anyway - then what is it FOR ?

0700700

it doesnt give you full control, for that you have a manual. it still decides what to do if it thinks you are a daft *(&(*&