540i Auto gearbox - slight yerk when coming to stop

I have this problem on my 2001 E39 540i with steptronic. When approacing stop sign, as soon as speed drops to walking pace, gearbox "jerks" into lower gear (i assume first gear). This happens when car is at normal operating temp. When aircon is on, this does not happen. Upon researching this problem found that on other forums it is quite well known. Apparantly the solution is to have the idle speed without aircon operational set to 100 revs higher than what it is at the moment. As the engine idles at slightly higher revs when the aircon is on, this problem is non existent if you drive with the aircon on all of the time, which i do not.
My question is, is there someone out there with the necessary programming kit to perform this adjusment who will not charge me an arm and a leg for the service?? In other words, someone other than a BMW dealer?

Where are u?

Convert to manual

Close to Cape Town - small town called Hermanus

Solo Man said:

Close to Cape Town - small town called Hermanus

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Nice place, I have quite a few clients there and around...

About 150km am I right?

Truvalu, exactly 100km from Cape Town airport.

The higher idle speed will irritate you more, because then it thuds and "yerks" into gear instead from N or P

rick540, i would like to change the idle speed when aircon is off, to same idle speed as when aircon is on. At the moment there are no jerks or thuds when aircon is on and you put it in gear. Should be the same at same revs without aircon, shouldn't it??

hmm, I don't think you can acctually change the idle speed with any bmw software, you will most likely need to fit a uni-Q chip, or get your gearbox software upgraded to fix the problem... I had the same problem, but I decided to do a manual conversion which I had planned in anycase so it eventually all worked out nicely

As long as the jerk doesn't get out when the car stops...

I have noticed my 540i starting to do something similar when I moved between the P/R/N/D a very noticeable jerk when engaging, how do I resolve that?

To be honest I do not think it's idle speed related, even though that may cure the symptom by causing a little more slippage during engagement of a gear. 100Rpm is about 30 - 40 Nm torque on that V8, and that's a lot extra at idle.

I would go for a transmission oil change first, as old oil makes auto transmissions "grabby" and rough.

I agree, go for a oil change first.
The idle speed can be adjusted, it might fix the jerk but not the cause of the jerk.

IIRC, when Car Mag tested a new E39 530d, it had the same jerk when coming to a stop - I'm too lazy to go thru my archive now to find it, but recall looking it up when my ex 530d did this.

BTW, my current X5 also does this and I was told it is normal on the 3.0d with 5 speed Auto gearboxes due to the amount of torque these engines produce - not sure of the 540i though.

msm said:

IIRC, when Car Mag tested a new E39 530d, it had the same jerk when coming to a stop - I'm too lazy to go thru my archive now to find it, but recall looking it up when my ex 530d did this.

BTW, my current X5 also does this and I was told it is normal on the 3.0d with 5 speed Auto gearboxes due to the amount of torque these engines produce - not sure of the 540i though.

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Mine (530d) does nothing of the sort. Possibly a software update might resolve the issue...

Lets see when the newest for your box was released...

Control module for 540i is GS 8.60.2, latest SW in NCS EXPERT is 12 Feb 2002. I think you should get an update.

I have the exact same problem on my 540i ,Have been told this can be fixed with a transmission software upgrade but I'm a bit sceptic about this,it is realy frustrating.

cool, I have my auto gearbox computer available if anyone finds theirs is faulty ... will need to be re-coded, which is very easy..

Clutchplate, are you saying you can program my gearbox if i bring the car?

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Sorry about that one. Just realized that you have a spare gearbox computer since removal of the auto and changing to manual

Have the oil and filters changed in the box first... The 'lifetime' fluid in the box has a limited life expectency, I learned that the hard way... Had to rebuild my tranny. If the car never did it before and is now starting, someting is wrong. Also look at the diff bushings... Mine was warn on my e46 and also made the car jerk when it slipped into a lower gear.

But trust me on the gearbox oil... a must to be done every 50000km, no matter what the Stealershiprs say.

Since I have bought Solo Man's 540i, thought I'd add to the thread.

Yup, the jerk was there, which he told me about before I purchased. Started doing some surf research but wasn't too concerned until a THUD and almost complete loss of revs at a stop street!!

Suddenly my research took on NASA proportions...hardly wanted the gearbox to fall out from underneath me.

Seems to me that this issue is not isolated to 540i's [ok, we knew this], nor to BMWs. And a lot of guys are struggling for answers.

Without ANY technical documentation to back me up, I will take a flyer and say the following:

Most guys do a complete transmission fluid and filter replacement, which seems to alleviate the symptoms for a while - but the problem returns in many cases.
Many either do or are thinking of doing a software upgrade to the transmission. Again, the results vary.
Few drive the car in Sports mode and fewer still use the Steptronic option [my opinion from what I've read so far - Ken Rockwell being my best example who calls the Sports Mode matter "pokey", if I remember correctly].
The Adaptive Transmission may be the problem if you have quite varied driving to do, like stop-go-stop, 30kms to work, stop-go-stop. Hmmm...

So, I figured I'd give the car a go in Sports mode. According to some, it saves wear and tear on the transmission due to fewer up shifts [no talk here about fuel consumption]. Bit of a pain with the higher revs going from one stop street to another. But no jerk....so far. Drove in Sports Mode to Cape Town from Langebaan. The car handled the stop go trafiic with no issues. Did not once put it into normal Drive Mode.

Ok, then got adventurous and used the Steptronic for the first time. Well, for me there is no other way of driving this car. I use the revs as I want to , change gear as I want to and am always "protected" from over revving by the very same gearbox that thuds at me in Drive Mode. Is the issue resolved? So far, yes, since I probably will never use Drive Mode again. But I will have my gearbox fully refreshed with oil and filter and have the valve body checked. I will also have the software updated if it can be done somewhere in Cape Town.

There was a lot of chatter on the net about driving style, particularly with regards to throttle sensitivity and some of it around the Adaptive Transmission Control. My view right now is that one has to adapt oneself to this type of car [gadgets 'n all]. If you have a jerking problem, I suggest working around it, as technical resolution seems to elude many.