Correct creation of the adaptations for the engine, gearbox, and other modules is unduly underestimated. The current hub will work unsatisfactory; there could be (and usually are) error messages recorded. The replacement of as if damaged spare parts does not help.
Every logical-minded person at this moment asks – where is the problem? The correct adaptation needs to be created! Problem solved!
What could be more simple? In this entry – what (unexpected) difficulties appear in this stage – creating the adaptations. This time – regarding the engine and the automatic gearbox.
The first problem – although the re-adaptation (both for the engine and gearbox) should be performed after each repair or even serious maintenance (for example, for the engine – if there were group misfires; for the gearbox – if the oil has been changed and shifting is not perfect), very often ISTA does not even mention this stage! It is not really clear – does the BMW AG rely on, that the maintenance specialist knows that (that the adaptations should be made), or relies on, that everything will somehow work out.
Yes, at SB (servicing block diagrams), the re-adaptation is typically mentioned as the last stage, but – no more exact recommendations. Obviously, BMW AG considers that the maintenance specialist has to use information from TIS. What is written in TIS?
The situation with the re-adaptation algorithms of the gearbox is pitiful. There is not even an indication to the Service manuals of ZF, manufacturer of the gearboxes. Good news – these Service manuals can be found on the Internet.
With the re-adaptation algorithms of the engine, the situation is a bit better. The engine should be held idle for several minutes; the should drive on the highway for some 5 minutes. Both stages should be repeated several times. As if simple and easy to understand.
At this moment, I would like to mention the first problems, which typically appear:
a. most part of the users and dealer specialists of BMW AG see the option “delete the adaptation”; press it, and return the car to the customer! Because it is not written, it is not allowed to do so. There is no categorical requirement immediately and correctly to create the adaptations. Only in SB, I have seen the requirement to perform a test drive and evaluate the new adaptations. Unfortunately, SB is limited access information and as the practice shows – even the specialist of BMW AG dealer centers are using on infrequent occasions;
b. ZF gearboxes have at least 4 different software groups; each requires an individual re-adaptation algorithm. Despite this – there is no information in TIS or in any other BMW service documentation;
c. N43/N53 engines are much more complicated than any other petrol engine manufactured by BMW, but these engines are no other/wider/more specific re-adaptation recommendations. For these engines, the injectors are measured both in Homogeneous and Stratified charge injection modes. In each of these modes, several tests of the injectors are performed. But the dealer center specialists have no access to any data of the injectors! Completely nothing!
Thanks to these flaws, in most cases, when the engine and the gearbox are “re-adapted,” the result is very incorrect. The gearbox switches with jolts, the engine – vibrates, shivers.
But – there is one more much serious problem!
This problem is – the adaptation of the flywheel of N series engines. During the creation of this adaptation, each tooth (its differences from the ideal) of the flywheel tooth wheel is measured, and the crankshaft sensor – its differences from the ideal. This adaptation is indispensable for all N series engines. This is the base of all adaptations and should be performed as the first one.
Why was this adaptation introduced?
a. in N series engines, the crankshaft tooth wheel has become much smaller – it is placed not outside the engine block (as for older engines), but inside it. Accordingly – the tooth also has become much smaller. Accordingly – the significance of the technological difference (from the ideal) is much higher;
b. in N series engines, a more efficient system of measuring each cylinder’s mechanical efficiency is introduced. And at the same time – circumstances, which affect this mechanical efficiency, have arisen: either Valvetronic or piezo injectors. Thanks to these obstacles, the adaptations of the flywheel have much more significance and impact than previously.
How are the flywheel adaptations performed?
There are 1 .. 2 sentences regarding it in TIS. The adaptations of the flywheel are made in Overrun mode if it lasts at least 10 seconds. Making the adaptations continues during all “life” of the engine. And – that’s it!
What are the consequences if the adaptations are made incorrectly?
DME switches off most of the functionalities. It is not able to even out the mechanical efficiency of cylinders; the engine vibrates. Individual fuel mixture of the cylinders is made completely incorrect. CO catalytic converters are overloaded (and prematurely) damaged. Misfires can appear. Data of injector adaptations, LTFT of the fuel mixture are incorrect. The engine runs completely unsatisfying.
One of the most important questions – can the flywheel adaptations successfully for “by themselves”?
Unfortunately, the answer is – no, they can’t! The situation with vehicles equipped with the automatic gearbox is a bit better. If the car owner regularly drives on the highway and reduces speed by releasing the accelerator pedal (but does not presses the brake pedal), after a certain time, DME will finish the creation of the adaptations. The problem – during that time already all other adaptations (injectors, fuel mixture) will already be created incorrectly. For those, who drive only in the city or for braking actively use the brake pedal, the situation is worse. In this case, the flywheel will not be adapted for a long time. Definitely – even when the flywheel will adapt, the engine will continue to vibrate and shiver.
The worst situation is for those who have a car with a manual gearbox. In this case, everything will depend on the driver’s habits. If the driver does not use Overrun mode (braking with the engine, not using the brake pedal), the flywheel will never be adapted! DME will continue to run in a complete limp mode endlessly!
To make the situation even more “easier,” BMW has taken care that the dealer center ISTA’s diagnostics equipment, the learnbit of the flywheel adaptation can not be visible. The diagnostics specialists of the dealer centers even don’t have options to perform correct engine adaptations! First – not ISTA nor TIS does not mention how the flywheel should be adapted; second – the diagnostics specialist has no tolls to control this process! How so, BMW?
The only good news: in INPA, learnbits of the flywheel adaptations can be seen:
Unfortunately, this learnbit helps only in cases when the diagnostics specialist uses (or is allowed to use) INPA; understands the meaning and importance (and the adaptations of this learnbit (and the adaptations in total). As we know, the specialists of the dealer centers are not allowed to use INPA. Unfortunately, the attitude of the staff of dealer centers (and even many specialized service centers) – “no, we don’t make adaptations. We have no time for that. We don’t see the meaning of this procedure, and we are not additionally paid for this procedure…”
It is sad, but many engines and gearboxes continue to work completely unsatisfying because there is no correct re-adaptation performed because of one elementary reason.