My experience with BMW N series engines (MSV/MSD series management units) shows, that at least in 80 .. 90% cases the replacement of the injectors is unjustified.

After such (unnecessary) replacement is two possible scenarios:

a) performing this replacement, also damaged knots are repaired (for example, preventively replaced spark plugs, coils or, for example, CCVV), deleting of adaptations and re-adaptation is performed and – the performance of the engine really improves;

b) replacement of the injectors is performed incorrectly, no improvements.


One of the examples, how to NOT encode the injectors:

Statistics regarding this current video: more than 6000 views, 30 “like”,0 – “unlike” (first “unlike” – mine). Sorry, but couldn’t resist showing my attitude.


What essential mistakes did the diagnostics specialist admit?


1. Stored incorrect data of injector coding. As mentioned here, after storing last digits of DME injector coding are different. If we try to input these stored data repeatedly:

a) ISTA D will not confirm new data;

b) INPA will allow the input of new data, but will not use them; the creation of adaptations will be disturbed.

If we will use these data for comparison (for control – are the correct data entered), the incorrect conclusion will be – data are stored incorrectly!


Here – data, which were entered.


And here – data, stored by diagnostics “specialist”.

2. Adaptations – old ones were not deleted and new ones were not created.

If old adaptations are not deleted and new ones are not created (flywheel adaptations + all types of LTFT: bank offset and multiple, cylinder offset and multiple), the engine will continue to work in the limited functionality mode:

a) no individual adaptations of cylinders are performed, as a result – persisting vibration of the engine, in separate cylinders – the number of misfires increases, error messages regarding fuel trim, CO catalytic converters can appear, the performance of the engine will be uneven;

b) creation of other adaptations (fuel trim of banks etc) is disturbed. As a result – all problems, which were mentioned above till even lighted-up EML indicator in KOMBI.


Unfortunately, none of 6000 viewers has pointed it out, only one (!) had a question, why the entered data are different from stored data. Unfortunately, there was no response from the “specialist”, who performed the coding.


I regularly receive e-mails with complaints, that after previously done replacement of the injectors the desired result was not achieved: there are no improvements. So, shortly, once again,

how the replacement of the injectors must be done.


1. Encoding of flow-rate data of the injector:

a) it’s recommended to use ISTA D;

b) if you use INPA: check the entered data very carefully (INPA don’t perform an integrity check of entered data); if you encode injectors for 4 cylinder engine, use this link to define the order of cylinders;

c) store the data printed on injectors, not the data, displayed by ISTA D/INPA after encoding.


2. Deleting of adaptations:

a) if you use ISTA D: follow the Test plan sub-task, which suggests deleting the adaptations. If for some reason the sub-task is not created, use INPA to delete the adaptations;

b) if you use INPA: delete all adaptations ../F8/F2/Shift+F9 (status – ignition: ON; engine: OFF)*

*for N43/N53 series engines it is recommended to perform the desulphation session of NOx catalytic converter before replacing the injectors.


3. Creating new adaptations:

a) flywheel adaptations;

b) bank offset type and multiple adaptations

c) cylinder offset type and multiple adaptations (for N43/N53 series engines – Homogeneous and Stratified charge modes).

How to create the adaptations correctly, read here.