BMW recently flashed the software in my car due to some other issue (luckily solved now). Either the new software or something else triggered a new problem. I started noticing very light, but annoying
hesitation and jerking at slow speeds – when going over speed bumps for example.
Here is a link to the video:
http://www.youtube.com/watch?v=RiC6Zlh0F9I
- the car is slowing down from 40 km/h down to 20 km/h by itself (gearbox downshifting and engine breaking is quite good in Sports Automatic gearbox);
- at 20 km/h the RMP goes suddenly down to around 600 (idle RPM) and engine breaking seems to stop;
- when accelerator is pressed, the RMP goes up to 1200, however the speed does not increase (hesitation);
- then the car slightly shakes, the RMP drops to 1100 (JERK) after which the car accelerates.
It seems, that the gearbox disengages the gear at 20 km/h and if accelerator is pressed it engages the gear again, which causes the issue - like a manual tranny when clutch is let go before completely engaging.
I test drove a different car with a local dealership and it DID NOT have the same behaviour - gearbox continued breaking down with engine below 20 km/h and did not disengage the gear so abruptly. It was a normal gearbox though, not a sports gearbox like mine. Unfortunately, there are no cars with sports auto gearbox around to try.
….
Does anyone else with 525d and Sports Auto gearbox experience the same? Does your RPM goes to idle at around 20 km/h and you feel jerk when pressing accelerator again?