In this entry, I will continue the story about N series engines and their adaptations. Let’s go a step further. Imagine that we are (a bit) more conscientious employees, and we follow the order from ISTA D/+ to perform the adaptation process. We delete the old adaptations and perform the drive, sometimes stopping for some minutes. We do everything, as described in ISTA D/+and TIS.
A BMW owner approached me with complaints regarding the uneven performance of the engine after repair and re-adaptation. Here, the example, how does the learnbits of injectors for the N53 series engine looks alike after one such adaptation process, which was done according to the recommendations of ISTA D/+:
Hmm. How so? Not even one learnbit is colored?
No offset type, no multiplicative type LTFT are created? The control probes are not heated up?
Even the integrators are 0? So – even the wideband probes are not working! DME is working on open-loop mode!
Here – in Homogeneous mode, no injector tests are performed!
Also, in a Stratified charge, no injector leaking, no atomization quality/flowrate tests are performed!
Un here – the flywheel also is not adapted!
It turns out that DME has not even started to create any adaptations. How so?
There could be several causes for that.
a. at first, the flywheel should be adapted first, then DME should be “put to sleep”; then the new driving session should be started. Put the DME to sleep means – turn off the ignition; turn off all other consumers (even the alarm lights, etc.), wait, till the Start/Stop lightning is turned off. If the flywheel is not adapted + DME put to sleep in the existing driving session (directly after deleting the adaptations), DME does not start to warm up the Lambda probes; does not create any adaptations. DME waits for flywheel adaptation creation and the possibility to “sleep”! Unfortunately, not ISTA nor TIS does not say any word about this!
b. last digit of the injector coding is the data checksum. This checksum is intended for protection against the input of incorrect coding data. Yes, ISTA D/+ controls; if the data are correct, it is impossible to input the wrong data. But, there is no problem in inputting wrong data with INPA. Unfortunately, ISTA D/+ does not give any warning if previously the wrong data with INPA are put incorrectly. Accordingly, there is the following situation possible – a long time ago, someone put the wrong injector data via INPA. Still, now no sign would give any indication regarding that. Unfortunately, such incorrect data are completely paralyzing the work of DME. For a long time (even “going to sleep” several times), it does not start to warm up the probes, runs on complete limp mode; does not use injector encoding data; does not create a range of adaptations. The engine vibrates, shivers. And no warnings regarding problems with the injector encoding data!
c. and finally – a common problem for all previously mentioned: ISTA D/+ in no way controls if the engine’s readaptation is successful. There are no step-by-step recommendations! There is no type of control, are the basic adaptations created or not. There are no warnings if the DME has not even started to create the adaptations!
In my opinion, this is a shocking example, how irresponsible BMW AG treats important procedures! Of course, alls these problems cost a lot of money (solving problems with vibrations, shivering), time and nerves, fighting the unsolvable problems. Additionally, this situation is not solved for more than 10 (!) years!