If you are one of them who drives BMW with N43 and/or N53 series petrol engines, the most likely you have experienced rough run, misfires and never-ending stories with injectors, spark plugs and ignition coils replacements.
In our blog, we reveal most popular and well-hidden cause of these problems. We also provide cost-effective and long lasting solution.
We recommend to start with article who describes sentence:
The most woe of N43/N53 series engines: uneven operation – is well known to all interested, enthusiasts and repairers.
Yes, sometimes spark plugs, ignition coils and injectors are ones to blame. But one tricky cause is hiding, and nobody mentions of it. What it could be? Read more..
To each BMW enthusiast, we offer Online diagnostics for N43/N53 engines.
What does it mean?
Most popular reasons of rough run.
How to handle the situation, when N43/N53 has started to shiver.
In this entry: step-by-step diagnostics of, possibly, one of the most complicated engine management system of all times. Each of stages is kept as short as possible, references to previous posts for much more detailed information will regarding each knot/ theme be inserted.
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Entries relating NOx system – NOx catalytic converter and NOx sensor:
Unfortunately none from available diagnostic programs don’t gives a clear view, in which mode does N43 and N53 performs on current moment AND which modes are allowed. For this reason we have to use several indirect evidences and parameters.
First impression – information, in which mode the engine (N43/N53) operates you can find using INPA. Read more..
More about basic operating principles of NOx catalytic converter you can read in N53 series engine after-sales training material or in any description of non-BMW engine, which performs in Stratified charge mode.
Here I will pay attention to observations from “real life”, which quite essentially differs from official newsletters. Read more..
I get more and more questions regarding the topic of NOx catalytic converter. Some askers wont to change the exhaust, removing this catalytic converter; some are interested in the normal performance of the engine is possible without NOx catalytic converter.
MSD80 records this message, if the mathematically counted parameter of sulfur “poisoning” is significantly higher than the norm, and the regeneration or catalytic converter is not performed/not possible. Causes for such situation could be:..
Error message 30E9 is specific, and it could be registered only in error message memory of MSD80 control unit for N43/N53 engines. Only these engines have NOx system with NOx catalytic converter included in it.
Why the error message 30E9 is registered? Read more…
Few times per second MSD80 sends command or data request to NOx sensor. One hundred times per second NOx sensor “answers” to MSD80: execute required commands or sends measured data.
When fuel consumption grows, most probably, the rough run of engine has also started…
The NOx sensor is comparatively quite expensive spare part, it’s price is around 450 .. 500 EUR, but work-life: very limited.
How to evaluate the performance of NOx sensor?
All information about specific problems of N43/N53
Not without a reason, BMW AG in their instruction how to perform their engine exhaust test highlights the specifics of N43/N53 engines.
In this entry I will compile recommendations, which have to be taken into the account, buying the car with N series engine.
How to get N43/N53 to perform as new?
Entering these error codes in Google search engine, the output is 20 .. 30 thousands of entries. And no wonder, because…
This entry will be dedicated to the topic:
how important is for all N43/N53 (sub) systems to work perfectly. This time we put the accent on “all systems” because there are no unimportant systems!
It is clear, that the engine with direct injection has problems with carbon residues in the intake manifold because the fuel (as for “usual” engines) does not clean’s it.
Several themes will be merged in this post, but it’s necessary, to explain the principles of performance of the engine management system.
Let’s start with several interesting issues regarding coding of injectors.
As already mentioned in other entries, modern engines are performing the measurements of mechanical efficiency in idle. Measurements are done, taking into account short-term speed changes of the flywheel.
This time – more about the Stratified charge, because data of cylinder-individual correction in Homogeneous mixture mode, unfortunately, are not available. Accordingly – in case of any problems, we have to investigate, how the engine behaves in Stratified charge mode.
INPA used the same loader both for N43 and N53 series engines. Thereby – if the N43 series engine is diagnosed, some questions regarding menu, where the performance of injectors/cylinders is displayed, arise.
Many people are asking – why the misfire algorithm tests for different software releases were performed? Why it is so important?
DISA is used also in other/previous BMW engines, not only N43/N53, so here we will mention only nuances, which are topical exactly for these engines.
For N series petrol engines, electronic accelerator pedal, and electrical throttle are used. Nothing revolutionary new, so I will pay attention only to some nuances.
When the weather becomes warm, more and more BMW drivers are enjoying driving pleasure, offered by BMW. More and more I receive e-mails – there is suspicion, that the engine doesn’t develop max torque/power. What to do in this situation?
Since long ago, BMW uses engine management systems of both brands – Siemens and Bosch.
What concerns petrol engines (4/6 cylinder versions), initially Jetronic/Motronic solutions from Bosch were used…
Performing diagnostics of several N46/N55 series engines (with Bosch management units), the problem, which perfectly fits in the theme of this entry, became clear.
What to do, when the good idea fails?
Try to fix it, solve it? Yes of course. How does Siemens (the BMW AG partner) succeeded with solving the Rough run problem for MSD80? Very poor.
Never ending story about N52/N53/N54 and family of 4 cylinder N series petrol engines and troubles with even running.. I believe, each owner of car with any engine mentioned has seen names mentioned above in error message descriptions! There is a legend, that the engine of this series running smooth – it’s mission impossible.
As mentioned in previous posts, the MSD80 is much more complicated engine control unit than one before (also MSV70/MSV80), and it makes sense, that such complicated unit has it’s flaws (more about it – read here), and also software updates are required.
MSD80 is a very complicated engine management system. Times, when the engine management system was performing specific, easy to understand algorithms, are gone for good. The engine control units of present moment are specialized, high performance computers, which performs several tenths of tasks at the same time.
Already for a longer while I had an idea to upgrade the software for my N53B30 U0. I was discouraged by thought, that the engine already has chip-tuning performed (for this current version, the benefit could be quite impressive: around + 50 hp, around + 40 Nm – it’s worth it, because the result is almost identical at the most powerful version of engine).
BMW engine diagnostics cases:
Many have heard about HPFP (high-pressure fuel pump) recalls in the beginnings of N43/N53, also for vehicles, which are in use now, error messages regarding fuel pressure are very often. Unfortunately due to faulty diagnostics, very often HPFP is mistakingly identified as faulty fuel supply element.
This theme applies not only to engines of series N43/N53, but also other petrol engines of BMW, which are equipped with VANOS.
The oil pressure for N43/N53 series engines is controlled by oil pressure sensor, which is located after the valve (solenoid). The valve is managed via DME by PWM and defines necessary oil pressure, accordingly to engine temperature, RPM, load.
In simple cases, MSV/MSD engine management units identify damaged Lambda probes, using self-diagnostics, marking the relevant errors. Unfortunately quite often there are no error messages, but still the engine has problems with maintaining the fuel.
The defect, mentioned in this entry, is quite rare. But in my practice are several cases with exactly this defect. It is very hard to identify this current defect…
This post best describes N43/N53 series engines – their complicated engine management, specific nuances in management performance and diagnostics.
The patient: N53B30.
A few months ago during the longer driving session, uneven performance of the engine was observed. Inspection of misfire counters with the ELM327 adapter was detected, that there are increased count or misfires in cylinder No.6.
One car with N43 engine got lucky – it happened to get to qualified mechanic. It turned out, that valve seals had lost flexibility, exhaust valves were swimming in oil. Oil in large amounts was found also in exhaust.
After engine repair (replacement of valve seals, prophylactic maintenance of engine head, new seals for exhaust).. Read more..
This time the story about classic of BMW engines.
Yesterday I took the opportunity to join an interesting case: E39 with M54B25 engine and, accordingly, MS43 Siemens control unit.
I/K/P BUS (9600 bps), D BUS (9600/115.000 bps), BSD (Bit-serial Data Interface) (1200 bps), Lin-bus (9600/19200/20000 bps), DWA-bus (9600 bps)…
Today I had the chance to be present in quite interesting case, where several mechanics were not able to find the cause of problem.
Entries relating adaptations:
In this entry you will find information about short-term fuel trims and long-term fuel trims. Description applies not only to N43/N53 engines, but to all progressive BMW engines.
Adaptations of flywheel is the basic for all adaptations. Probably, the most important of all adaptations. This article applies to MSD80 (MSV70, MSV80 will be the same), other management systems can have differences.
What does it means – to perform adaptations?
To perform adaptations: to create an initial maps for all management systems (long-term fuel trim map, ignition map, etc.) and coefficients (multipliers for cold engine fuel corrections, etc.).
If the engine performs as intended by the manufacturer, repair specialist don’t have to worry, how the adaptations are created. This is the only way, how to understand the total vacuum of information regarding creation of adaptations for MSD80.
The theory in practice:
What is Lambda?
Lambda (AFR) is characterizing relationship of air/fuel ratio. For example…
The oxygen sensors (Lambda probes) perform the control of exhaust gases and are one of the most important parts of petrol engine. The modern BMW engines use 3 or 4 oxygen sensors.
For check up of exhaust gases oxygen sensors are used. Long time ago is was zirconium narrow band Lambda sensors (in the beginning – without heating, after – with additional heating, which allows probes to be ready more quicker and also ensures more accurate data)..
In many ways, N43/N53 series engine is a leader of BMW technologies.
It’s control system MSD80/81 can work in several operation modes..
The summer is here, and also overheating problems of the engines also. In this entry – basics of cooling for all most popular BMW engines.
In several entries, the term “closed loop system” is mentioned. Now it’s time to explain bit more about this notion.
BMW AG in after-sales material mention, that thermal management of N series is directed by DME.
There are several work modes.
In this entry – a little about CO catalytic converters and exhaust gases.
Typical content of perfectly performing petrol engine…
The exhaust systems of N43/N53 series engines are equipped with 2 or 4 catalytic converters:
1 or 2 CO catalytic converters (1 piece for N43 series engines, 2 pieces for N53 series engines) and
In case, someone decides to register the injectors… Or – if the engine has unexplained problems with long-term trims (they last very long, are not able to be finished; the engine has permanent vibration even with completed long-term trims etc.; MSD80 has no error message records).
Vehicle self diagnostics is developed to facilitate the finding of defects in vehicle electronics systems. Each module of system continuously controls the sensors, actuators, working ability of different modules, in case of problems the system records error messages and/or modifies the operation algorithm..
When first electronic management units for the engine management were introduced (for example, Jetronic), they were analog, without any possibility of self-diagnostics.
How to interpret misfire counters data.
WWW. What Went Wrong:
Many people are opposing – it’s not possible, that authorized dealer of BMW AG can not detect defects for engine, manufactured by BMW AG!
So, for today I’m going to pretend to be a diagnostics specialist from authorized dealer center.
In this entry – diagnostic options, available with ISTA D. ISTA D is the main tool of dealer’s service center. Special attention will be paid to compare possibilities of ISTA D with INPA.
Manifestations of defect – uneven running of the engine, misfires.
Checking error message memory, very often you will find error messages regarding fuel trim of bank No.1, CO catalytic converters of bank No.1 and/or trim of Lambda probes…
If the performance of any injector is inappropriate in case of warm engine, it could be easily identifiable, using INPA. For example, using data of cylinder efficiency (../F5/Shift+F6/F3), the amount of correction applied to each cylinder (../F5/Shift+F6/F1), etc.
When the weather gets cold, more and more often problems with the performance of cold engine arise. What to do, if the situation turned out to be more complicated.
Replacement of ignition coils for direct injection engines is very usual operation. It goes without saying – as refilling the window washer fluid. The engine is shaking again? Let’s change ignition coils – and done!
In the century, when humans are planning to go to Mars, it doesn’t seems logical, that BMW was not capable to create stable and safe engine ignition system. While using my test stand for ignition coils, I noticed strange nuances in coil’s performance and decided to research this situation in a real engine.
In my work, I stick to the principle, that the replacement of the component should be reasonable. Accordingly – before performing the replacement, it has to be checked, that the current element/knot is damaged.
Petrol engines of N series uses electric water pump. Older ones use pump with 480W power, for newer engines the power of it reaches 700W.
The crankcase ventilation system is used in all nowadays engine. It’s task is to seize the vapours of oil and fuel and drain them to inlet manifold for repeated burning.
Unfortunately the understanding, how exactly this knot works – most often it’s limited with “leveling the pressures”, which is not true. Read more..
Has BMW AG developed correct test procedures? Has the N43/N53 series engines learned something?
Very simple task – as relaxation. Not only users of BMW E60, but also owners of other BMW models are complaining, that the windshield washing is not OK.
Even YouTube videos don’t give a clear view, how the windshield should be washed.
This time – very simple topic – checking the engine temperature, using hidden menu.
How to open this hidden section, you can find on YouTube, the procedure will not give any problems.
If MSD detects, that the oil supply system is not able to maintain required pressure (it means, the pressure value does not correspond to a required value longer than time X, or PWM value for time Y is not within required values), MSD turns on the emergency oils supply mode.
INPA is an irreplaceable tool for solving complex problems. INPA allows to read huge amount of data, which are not “seen” by other diagnostic tools. INPA ir irreplaceable, for example, in engine diagnostics.
Identification of vehicle and modules. Read more…
Engine diagnostics. Live data.
Engine diagnostics. Activation blocks.
Engine diagnostics. Adaptations. Test blocks.
Till now I was using one of the newest (stable) INPA versions – 5.0.6, which was using 1.001 loader for MSD80 diagnostics.
Today I got 2.023 loader and decided to test it.
As indicated by BMW AG, N54 engines, which are used in E60/E61, E9X, E88, E82, can have incorrect misfire indications (typically for cylinders of first bank).
Time ago, MS43 was very popular control unit of petrol engines. In this entry I will describe some nuances of diagnostics for MS43.
N43/N53/N54 and other direct injection engines uses not “classical” (coil – electromagnetic), but piezoelectric (material, which changes size, if affected by voltage) injectors. Piezoelectric injectors has been chosen because of instant reaction, which allows to execute multi-point (several injection cycles) injection mode.
While ago I began to take an interest regarding cleaning and diagnostics of piezoelectric injectors.Unfortunately then there was no options available – but now situation has changed.
How to encode a new NOx catalytic converter using ISTA D
How to encode a new NOx sensor using ISTA D
How to activate forced desulphation session of NOx catalytic converter using ISTA D or INPA