CIP20 has banished this little problem for me. I've done about 1000 miles since my update, and so far the throttle response has been excellent.

Whether things will go back to how they were, only time will tell. I hope not.

 

I have CIP20 and sometimes when the car is first started get the problem at a roundabout near my house whilst trying to pull into the early morning traffic. I would not call it a slam more like a delay with a jolt, however it is unnerving when trying to pull out quickly, especially as it is an intermittent problem.
I had exactly the same problem with my previous E-Class, that does not have a ZF box but a Merc. own design. It only seems to affect the car when the car is getting up to working temperature.
One day someone will have a serious accident through it though, and then were see what BMW have to say.

 

Thanks for the responses guys.

It has clarified a coulpe of things in my mind.

 

The slam that I experience in my 545i is far worse than a delay followed by hard acceleration. It is the sensation of being hit from behind by another vehicle traveling at approx. 5 MPH. The first time I experienced it, that is exactly what I thought had happened. It has occured approximately 5 times in 20,000 miles of driving. It happened most recently in DS not long after an upgrade to CIP 20 due to CCC failure. It has not happened since. Perhaps my ZF has learned not to do it, but more likely, I have been avoiding the driving condition that causes it. It occurs most often when I am in D or DS in a line of cars creeping to a Stop sign or freeway ramp meter light. I now tend to creep in M1 or M2 out of habit in order to avoid the slam. It seems to be due to a 2-1 downshift lag where the engine rev's up a bit in the neutral window and then rapidly clutches in first, however, I am not certain of this. In any case it is one frightening experience.

I reported all this to BMW AG, received a reply that they forwarded my email to the apporpriate party and have heard nothing since. This is not a problem that would deter me from owning the car, or even from buying another, since there is a work around for me that I don't mind. However, I think it is a definitely problem that should be fixed if at all possible.

 

COME ON PPL KEEP VOTING. Only 12 diesel owner voted by now?! I doubt there are on the forum only 12 diesel owners with steptronic transmission...