[sjed]

TLDR; On my N53 engine in my F11 the NOX sensor is failing, causing issues with stratified charge. My options are:

1. BMW OEM sensor (expensive)
   
2. Soldering a new NGK NS11A sensor (cheaper, high succes rate)
   
3. Buying NOXEM (mixed reviews, works but support is not great)
   
4. Software coding (controversial, but some success stories)

Does anyone have experience with software coding for this issue?

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For those not familiar, the N53 engine is a non-turbo engine that was used in the F11 before the N20 took over and the N54/N55 stepped in. To use all three injection modes (with stratified charge being the one reducing fuel consumption), it needs healthy injectors, plugs, and a NOx sensor.

The first two have been taken care of, with all index 11 injectors and the right type of plug and coil pack. Now, my NOx sensor is on the way out and it drops out of stratified charge after a while (confirmed by observing Lambda values).

My options:

1. BMW OEM: From what I understand, the NOx ECU is very likely still fine, so this would be a bit of a waste of money.
   
2. Soldering a new NGK NS11A NOx sensor to the ECU: The sensor is 1/5th the cost of buying BMW OEM. Most who have done this have been successful in restoring stratified charge.
   
3. Buying NOXEM: I hear mixed stories about their support, and from experience, I am also not too satisfied with their replies.
   
4. Software coding: Bimmerprofs say this is a bad idea, as the sensor also communicates over a LINBUS, which can't be simulated in the ECU. However, I have also read posts on multiple forums where software coding did restore all three modes.

So my question to you is, does anyone have experience with software coding? I have found two companies here that claim they can do it. I honestly can't be bothered too much with the NOx the car will produce in stratified charge and keep replacing the sensor and at some point the catalyst, so it would be the preferred option.