Q1: Why my car needs a NOx sensor?
A1: NOx sensor monitors the NOx amount in exhaust gases. Without these data, the engine disables Stratified charge and Homogeneous lean injection modes. As a result, fuel consumption grows. Also, there are some side effects if the NOx sensor is broken or disconnected (also if error messages relating to NOx catalytic converter are recorded): the engine starts shaking, rough run, and misfires appear. Problems with the NOx system can be the cause of error messages about fuel trim, Lambda probes, insufficient efficiency of CO converters, and misfires. For more information, read here.
Q2: What is the difference between the NOXEM NOx emulator and the OEM NOx sensor?
A2: The OEM NOx sensor measures a series of exhaust gas parameters, including the content of NOx in them. If the NOx catalytic converter has aged or is damaged, the NOx sensor determines it – the need to replace the expensive catalytic converter is inevitable. The NOXEM NOx emulator “informs” the system that the level of NOx in the exhaust is acceptable, regardless of the technical condition of the NOx catalytic converter, and there is no need to change the NOx catalytic converter anymore. NOXEM allows you to save more than EUR 4000.
Q3: What are the main differences between NOXEM emulators and ‘’usual’’ emulators?
A3: NOXEM does not ‘’cheat’’ all signals necessary for measurements. NOXEM measures all possible parameters in real time. Also, NOXEM does not use the ‘’record/playback’’ principle but generates output parameters based on a deep understanding and mathematical model of the NOx system. This manner guarantees the best possible performance overall conditions.
Q4: Is NOXEM safe for my car?
A4: Yes, NOXEM is absolutely safe for your car. NOXEM installation is ‘’plug and play’’ and does not require any wire cutting and/or specific connection to your car’s electronics. We have explored genuine data transmit protocol, and NOXEM responds the same as OEM-made NOx sensor. From the engine’s ‘’side,’’ there is no difference between the NOx sensor and the NOXEM NOx emulator.
Q5: Will emissions rise significantly if I will install NOXEM instead of OEM NOx sensor?
A5: The situation is a little bit more complicated than it looks at the first moment.
At idle, the N43/N53 engine can work in both Homogeneous and Stratified charge modes as well. In Homogeneous mode, NOx content is close to 0 (and is reduced by CO converters), and there is no difference between NOXEM and OEM sensors. If the Stratified charge is selected at idle, the NOx amount is small (because the amount of burned fuel also is very small). At idle, MSD80 does not make any decisions based on NOx content (i.e., does not control the efficiency of NOx catalytic converter) – there is no difference between NOXEM and OEM NOx sensor.
At loads more than 60% (corresponding driving speed: from 120 .. 160km/h, depending on engine) engine switched to Homogeneous mode and emitted NOx content close to 0. In Homogeneous mode, NOx content is reduced by using CO converters, not NOx converters. And again – there is no difference between NOXEM and OEM NOx sensors.
At low loads, NOx content corresponds to EURO4/5 if the remaining efficiency of the NOx converter is around at least 10 .. 20% because of the small amount of burned fuel and the high efficiency of the engine.
The worst region (from the emission side) is driving with speeds 70..120..160km/h while the engine performs a Stratified charge. In this area, NOx content could exceed the allowed limits if the remaining efficiency of the NOx converter is low. At the same time – the content of CO and CH is significantly lower compared with the same engine, working in Homogeneous mode (if there are problems with the NOx system).
Moreover – almost all of the N43/N53 series engines with NOx system problems (error messages related to NOx converter and/or NOx sensor) are working with serious unevenness – as the result of un-optimal fuel/air ratio and produce very high levels of CO and CH. Installing NOXEM solves problems with long-term fuel mixture adaptation creation, restores the correct fuel mixture, and reduces CO and CH content while the engine performs in Homogeneous mode.
Q6: Will I pass the technical inspection if the NOXEM 129, NOXEM 130, or NOXEM 402 is installed on my vehicle?
A6: Yes, you will pass the technical inspection if all systems (except NOx catalytic converter) are in working condition – NOXEM will not affect it in any negative way. On the contrary – if the NOXEM is in use, the engine will perform in Stratified charge mode, which significantly reduces values of CO and HC (and reduces the load to CO catalytic converters), measured in exhaust gases.
Q7: Is it possible to identify (during any type of technical inspection) that the NOx catalytic converter is damaged and the NOXEM is installed?
A7: No, it is not possible to identify it. The engine produces a higher level of NOx only under real load conditions. While the exhaust gases are measured, the vehicle stands still (independently of the range of RPM), and the level of NOx will be in accordance with admissible standards. Both visual inspection of a vehicle’s exhaust system and testing with specialized diagnostic equipment will not show any suspicious differences that the control systems of the vehicle have been modified. Moreover – regular technical inspections do not include measurements of NOx amount in exhaust gases.
Q8: If I use NOXEM, will I have fuel economy?
A8: Yes, the use of NOXEM will decrease fuel consumption by at least 15 .. 25% compared to the vehicle, which has problems with NOx catalytic converter and/or NOx sensor, and at least 5 .. 10% compared to a vehicle, which NOx catalytic converter has good performance, and there are no technical problems with NOx system components. NOXEM requires regeneration of NOx catalytic converter max rare (each 50 .. 60 seconds) and desulfation – with max low exhaust system temperature. Both conditions guarantee max low fuel consumption and max long work-life of the exhaust system.
How does NOXEM allow you to save fuel?
NOXEM allows you to save an extra 5..10% (usually around 10%) of fuel compared to the OEM NOx sensor. How? NOXEM initializes regeneration of NOx catalytic converter max rare – average after 50 .. 55 seconds. In the case of the OEM NOx sensor, the NOx catalytic converter is regenerated after 10 .. 20 seconds. During regeneration, the engine burns an additional amount of fuel to heat the NOx catalytic converter. The less often the regeneration, the less fuel “waste”. Also, desulfation sessions NOXEM initializes max rare – 3 .. 5 times less than OEM NOx sensor. In the process of desulfation also, an additional amount of fuel is burned to keep the temperature of the exhaust system high. Moreover, when using NOXEM, you can avoid desulfation sessions at all – it allows you to save both additional fuel and money.
Q9: If I will not like the performance of NOXEM – will I be able to go back to the original setup of the exhaust system?
A9: Yes, you can go back to the original setup of the exhaust system. If you use your right of withdrawal, Bimmerprofs will return the money you spent on NOXEM (read more in warranty terms). The NOXEM does not interfere with the structure of an exhaust system or management system structure, so anytime you want, you can go back to the original setup.
Q10: Which product should I choose?
A10: We suggest using realoem.com to specify the code of the NOx sensor by your vehicle’s VIN code. If you know the vehicle body code and series of the engine – check the description of NOXEM products. NOXEM 129 and NOXEM 130 are developed for the E series. NOXEM 402 is dedicated to the F series.
Q11: Are any additional procedures required after the installation of NOXEM?
A11: Several service procedures must be performed after the installation of NOXEM.
For E series (NOXEM 129 and NOXEM 130):
- if 30E9 error is stored: perform service procedure ‘’registering of new NOx converter’’ using ISTA D/+ first;
- clear errors;
- perform re-adaptation of the engine. Recommended software: INPA;
- evaluate new adaptations.
A possible alternative for re-adaptation (2 .. 4): ISTA D. If ISTA D/+ is used:
- perform service procedure ‘’registering of new NOx converter’’ (regardless of 30E9 error);
- perform service procedure ‘’registering of new NOx sensor’’;
- perform re-adaptation of the engine;
- evaluate new adaptations.
For F series (NOXEM 402):
- clear errors;
- perform re-adaptation of the engine;
- evaluate new adaptations.
Recommended software: INPA. Possible alternative: ISTA D/+
For further information, please refer to the Installation manual of the exact product.
Q12: Does the use of NOXEM differs from the exploitation of the original exhaust system installed by the manufacturer?
A12: No, the exploitation of NOXEM does not differ from the exploitation of the NOx sensor supplied by the manufacturer. The engine will perform all intended functions as with the original NOx sensor, including regeneration and desulfation of the NOx catalytic converter.
Q13: What is the resource of NOXEM?
A13: NOXEM uses only original Bosch sensors (newest generation), the work-life of which could reach 200 .. 300’000 km. And you will not have to worry about the resource of NOx catalytic converter anymore. Additionally, Bimmerprofs offers a lifetime warranty on electronic parts of the product (read more in warranty terms).
Q14: The error message memory of my car’s engine control unit shows the error message 30EA, and the specialist (in BMW service) says that the NOx catalytic converter requires desulfation. I live in a densely populated area and have no appropriate roads in near reach to perform the process (it’s necessary to drive at a speed of 110 km/h for at least 30 minutes). And also, the desulphurizing process requires some special activation and control of the process, where special diagnostic tools are necessary. Will NOXEM solve my problem?
A14: Yes, NOXEM will solve your problem. Only after each 7’000 .. 8’000 km (up to 10’000 km with the latest software releases of MSD80) you have to spend some 5 minutes and delete the information regarding sulfuring of the NOx catalytic converter, using ISTA D/+. There will be no need to look for a specific road section, no risk with penalties for speeding, no control of the desulphuring process – no money & time expenses.
How to encode a new NOx catalytic converter, read here.
Q15: After old adaptations are cleared, some new error messages appear. Did something go wrong?
A15: This is a normal situation. When adaptations are cleared, the following error messages* can appear immediately:
- error messages relating to DSC. Solution: drive for 10 .. 15 min, switch off the ignition for 2 .. 3 min, then turn on;
- error messages relating to throttle. Solution: turn on the ignition, press and release the accelerator pedal 3 times, then start the engine.
During the adaptation process (after old adaptations have been cleared), some error messages* can appear:
- error messages relating to fuel trim (bank and/or cylinders individually);
- insufficient performance of CO catalytic converters;
- Lambda probes (trim and/or signal);
- uneven run (Stratified charge and/or Homogeneous injection).
*these error messages in the exact situation do not indicate any problems with the engine performance.
After new adaptations are completed (after 5 .. 8 driving sessions for cold/warm engine, at least 200 .. 300 km), check the new adaptations and clear error message memory using INPA or ISTA D/+, if necessary.
How to perform adaptations read here and here.
Q16: Can I demount NOx catalytic converter after installing the NOXEM?
A16: Yes, you can demount the NOx catalytic converter, replace it with a silencer or install the custom exhaust. Detailed information read here.
Q17: Should the CO catalytic converters be in working order for N43/N53 to perform in full?
A17: Yes, the CO catalytic converters should be in technical order. If the engine management unit diagnoses them as not fit, it will record an error message regarding CO catalytic converters, and it will not allow the Stratified charge, and all benefits of engines mentioned before will not be available.
Q18: The price of the used NOx sensor is significantly lower. Is it worth buying it?
A18: The NOx sensor is a very sensitive and fragile tool. Much more fragile and sensitive to any type of overload, for example, of Lambda probes. Increased temperature, increased oil product content in exhaust gases, and water condensation have a huge impact on the NOx sensor and damage it. The average work-life of the NOx sensor is only around 50’000 km. We categorically don’t recommend purchasing a used NOx sensor – it won’t even be a short-term solution.
Q19: If I choose to replace the NOx sensor with the OEM NOx sensor, is it important to purchase the NOx sensor exactly from BMW AG/BMW dealer?
A19: Although all NOx sensors look the same (Continental produces them according to directions from NGK), each model has its own separate data exchange protocol. MSD80 will not understand inappropriate data from a sensor. Also, each NOx sensor contains ID information. If MSD80 receives data regarding an inappropriate NOx sensor (for example, intended for another car model, fuel type, or software release), it will not even turn this sensor Online – it won’t even try to read data sent by the sensor.
Q20: My car has problems with the NOx system. In addition, the error message list contains error messages relating 5th cylinder (misfires); also, the error message relating efficiency of the CO catalytic converter is recorded. Should I replace injectors, ignition coils, and spark plugs first?
A20: In case, if there are problems with the NOx system, MSD80 creates totally incorrect cylinder’s individual LTFT, and usually following error messages appear:
29D1: misfires of 5th cylinder;
29F5: efficiency of CO converter below the threshold, bank 2.
Also, error messages regarding fuel trim (especially for bank 2) usually appear. Problems with the NOx system also can be the reason for error messages relating to (individual or all) cylinder’s misfires; low efficiency of CO catalytic converter, 1st Bank; Lambda probes; incorrect fuel trim (cylinder’s individual or Bank).
Problems with the NOx system (NOx sensor and/or NOx catalytic converter) can be the reason for following error messages:
29CC misfirings, several cylinders
29CD misfirings, cylinder 1
29CE misfirings, cylinder 2
29CF misfirings, cylinder 3
29D0 misfirings, cylinder 4
29D1 misfirings, cylinder 5
29D2 misfirings, cylinder 6
29E0 fuel mixture control
29E1 fuel mixture control 2
29F4 catalytic converter conversion
29F5 catalytic converter conversion 2
2A2B fuel mixture control
2A2C fuel mixture control 2
2C31 Lambda probe in front of catalytic converter, trimming control
2C32 Lambda probe in front of catalytic converter 2, trimming control
2C7E Lambda probe behind catalytic converter, trimming control
2C7F Lambda probe behind catalytic converter 2, trimming control
etc.
None of these messages (in the exact situation – when/if the NOx system is damaged) usually has a real cause; all of them usually are the result of incorrect operation of MSD80. Detailed information read here.
Q21: How significant is it to keep the NOx catalytic converter clean of nitrites and sulfur? Could the clogged NOx catalytic converter impair the engine performance (torque)?
A21: The amount of nitrites accumulated in the NOx catalytic converter is measured in milligrams, but the amount of sulfur is in several grams. The critical boundary, when MSD80 considers that NOx catalytic converter is critically polluted with sulfur, is 3 .. 4 grams, which can not decrease the power of the engine in any way (the layer of sulfur on the walls of the catalytic converter can be measured in microns). Even in cases, when due to a damaged crankcase ventilation membrane, the engine had huge oil consumption, and the NOx catalytic converter was removed because of suspicion that it had been clogged because of burned oil, the suspicion didn’t prove correct. No improvements in torque were observed after disassembling the NOx catalytic converter.
Q22: I installed NOXEM in my car. After a long while (I’ve traveled more than 4000 km), the poisoning (with sulfur) parameter of the NOx catalytic converter has reached more than 2000 mg. Why it’s like that? Shouldn’t this parameter be with a lower value?
A22: MSD calculates the level of sulfur poisoning using the mathematical method – it increases proportionally to the fuel amount burned in the engine. If MSD detects that the NOx catalytic has perfect performance abilities (NOXEM gives exactly this information), MSD allows a very high level of poisoning (even 3000+ mg), and desulfation sessions are required max rare. Using NOXEM, intervals between desulfation sessions can reach even 6000 .. 8000 km (and “cleaning” of NOx catalytic converter will be relatively quick); at the same time, OEM systems (OEM NOx sensor and NOx catalytic converter with average performance) will require desulfation sessions even after 1000 .. 1500 km (when poisoning parameter reaches 500 .. 800 mg), and these sessions are relatively longer (NOx catalytic converter is “cleaning” much slower). Accordingly – using NOXEM – the sulfur poisoning parameter can reach a much higher level than in the case of the OEM NOx sensor, and that is normal – nothing to worry about.
