I decided to mark this one project between several hundreds of successful ones. Mark for several reasons. At first – this was one of the projects of successful cooperation with specialists of one of the local workshops. I performed initial diagnostics, specialists of the workshop – installation of the NOx emulator; the re-adaptation of the engine was performed in cooperation.
At second – the fight of the owner of the car till the choice of the correct solution was long and painful.
Vehicle: E90, N43B20 engine, bought in Norway with an engine defect.
Unfortunately, the local ‘masters’ didn’t manage the maintenance and repair of the N43 engine. Then it was decided to install an N46 series engine. Even the steering column has been replaced. When the ‘specialists’ didn’t handle the installation of the engine, however, it was decided to re-install back the N43 engine.
The engine was installed, but its performance was characterized by permanent vibration in an idle, unevenness, increased fuel consumption. The car has been in all possible services in an exact area, but without success.
In the error message memory – 30EA error message:
In several modules the mileage above 500.000 is recorded, incorrect FA configuration – consequences of actions of ‘professionals’.
30EA means – if the NOx sensor works (there are no error messages regarding it), possibly – we will succeed to clean NOx catalytic converter and solve all problems, performing only service procedure.
Also, other DME basic parameters were checked.
For example, Rough run data indicate permanent vibration:
Here, the 1-st cylinder – increased (-0.006) mechanical efficiency; 6-th cylinder – decreased (+0.004) mechanical efficiency. But, even seeing this problem, DME didn’t try to fix/avoid it.
Here, confirmation of the NOx sensor and catalytic converter are experiencing problems already for a long time – specific adaptations for Stratified charge are not finished:
Here, data of injectors in Stratified charge, idle:
The engine has never even tried to work in Stratified charge!
Why?
Let’s check data of NOx sensor:
Critical parameters are marked: they signal the sensor doesn’t switch to Online mode, despite required criteria (exhaust temperature, RPM, etc.).
Conclusion – the sensor has a hidden defect (very common for OEM sensors) – it is damaged. Due to this damage, unfortunately, no normal cleaning of NOx catalytic converter to delete the 30EA error message will be possible, also the normal performance of the engine won’t be possible.
Due to this problem, the engine doesn’t use economical Stratified charge mode (it has increased fuel consumption), don’t create adaptations – for this reason, there is vibration, shivering.
The car owner will have unexpected expenses – NOXEM has to be installed.
Specialists of the workshop installed NOXEM. Now it’s time to re-adapt the engine. At first, the old adaptations are deleted, then – new adaptations of flywheel and fuel for all modes are created. This task requires performing specific activities for around an hour.
Here, the engine again woks in fuel-saving Stratified charge mode after a break of several years:
And also correct data of NOx sensor:
Here, also the new NOx sensor confirms Stratified charge mode.
And now also the measurements of injectors in idle are performed:
Everything is fine with the injectors.
Also measurements or mechanical efficiency in Stratified charge mode: perfect!
I recorded a small video (idle, Stratified charge mode):
Evenness of the performance of cylinders-phenomenal! Differences between cylinders are not higher than +/2%! Here, how the BMW engine is supposed to work!
Fuel adaptations: correct, wideband probes are trimmed correctly.
Self-evident: the error message list: empty:
During the next few days, DME will create new adaptations for all performance modes – slowly the complete evenness of performance will be reached.
Yes, this repair was not the free-of-charge case, but it’s incomparable cheaper that re-installation of the engine!
