Re: All about Z4 (E89/ E86/ E85) thread
Folks, thought I share something. It’s elementary to most, but another lesson learnt in my auto resume…
Some 4 weeks ago, I was experiencing hesitation when moving off stationary, car taking a short while to find 2nd gear when moving from 1st gear, see rpm goes up while speedometer stays inactive for 0.5 – 1 sec (depends on how hard you rev).
Went to the commonly-stated BMW workshop (well, decided not to shame here), painfully described the symptoms to them. All three shops ran s/w scan and no error code found. These were their respective next steps of diagnosis:
Shop A: Didn’t even bother to drive despite my request, and recommended ATF change. Mentioned and insisted that it’s mostly due to ATF (even though I told them I had changed it 10,000km ago) based on his extensive experience.
Shop B: Test drove, and shrugged off the symptoms, and mentioned that its ‘normal’ and nothing wrong… alternatively, try changing ATF and spark plugs/coils. Either may help…
Shop B (again): Went to talk to shop owner, claimed to tranny expert. Without test-driving, mentioned that gearbox is most likely gone and is probably due to worn tranny ring bands. Mentioned that changing ATF will not help and should consider recon gearbox replacement before it get worse.
Shop C: Test drove, and shrugged off the symptoms, but at least ran in-depth software to look at my transmission valves… Analysis + waiting took about 30mins… Mentioned that no fault = nothing wrong mechanically and electronically, and mentioned that changing ATF will likely not solve the problem…
Can’t believe it’s my gearbox (5-speed auto, non-SMG) since its one of the more traditional trusty beemer 3L gearbox. Somewhow, it struck me that that these cars have ‘intelligent’ gearbox that adapt to our driving style. Google it, found the reset steps. Nothing to lose and follow the steps to reset my ‘transmission memory’.
Throttle Body Adaptation Reset for AT - BMW 3-Series (E90 E92) Forum - E90Post.com
From the link:
Throttle Body Adaptation reset. Resetting the Adaptive Driver Memory for the transmission.
Works with any car that has Driver Adaptive Electronic Controlled Transmission.
1. Get in your car, it doesn't matter if you close the door or not.
2. Turn the key to the on (not start) position, the position just before the starter turns over. BMW: press start button – foot off brake - all idiot lights on.
3. Press the gas pedal to the floor with the key in the "on" position. BMW: All idiot lights on.
4. Hold the pedal to the floor for five seconds, then turn the key back to the "off position". BMW: foot off brake press start button - all idiot lights now off (don't remove the key), then release the gas pedal.
5. Wait a full 2 minutes for a full electronic alignment. Don't remove the key.
6. Start engine, drive the car, notice the difference.
Bottomline: I went a complete cycle (aka the professional way and most complex way) before discovering the most fundamental solution. Was not impressed with Shop A and B way of working and their so-called ‘I know it all’ manner. Shop A is worse, made one big big assumption w/o wantng to test drive it, and offer the straightforward and $$$ remedy. I just refused to believe that tranny software reset is not in their ‘toolkit’. Well, knowing the basics sometimes can save some $$$. Just to share...