Target injection quantities, etc. 123d? (Reference vehicle data logged!!!)

Hello everyone,

still about: /viewtopic.php?t=25553

Can anyone tell me where I can find the target data for the 123d?

Fuel injection quantity, air mass, boost pressure, etc.

I couldn't find anything about it anywhere on the web.

Can I inquire about something like that from BMW? They probably don't like giving that information away, do they?

Sure, here's the translation:

"Thank you in advance."

LG,

Bo.

Hello,

In control loops, it is reasonable to read the setpoint and the actual value via diagnostics; otherwise, you might as well skip OBD altogether.

Best regards, Rainer.

dieselschrauber wrote:

Hello, In control loops, it is reasonable to read the setpoint and the actual value via diagnostics; otherwise, you might as well skip OBD altogether. Best regards, Rainer

Okay, cool. Then it's not going to be quite as difficult after all...

You're welcome.

LG,

Bo.

I recently had the opportunity to log some data... (see: /viewtopic.php?p=189899#189899)


Unfortunately, there's nothing quite as useful as measurement block 3-8-11 in BMW vehicles. Here are the data points that I logged, which I believe are relevant.

The air mass is always above the target mass (typically). Peak above 1400 mg/H).


Remarkably, both the boost pressure and the fuel injection volume exhibit nearly identical trends relative to their respective target values. There is practically no swaying.

Look closely; you might not immediately notice that there are actually two lines in each case.

In addition, there is a value for the current applied torque, and a value for the minimum limit based on both smoke reduction and torque limitation. "Here, I don't understand how the current torque could be above the limit... the calculated values are clear."

Hello,

Is that a 2-liter, 4-cylinder engine, right?

Overall, everything looks good except for the somewhat high air mass. However, I think that >1400mg/H at 4000rpm seems a bit too high for a 500cc single cylinder engine with 2500mbar of boost pressure. Given that BMW also relies on water cooling, I would have expected a value of around 1200mg/H.

Simple leak in the charge air ducts or the intercooler?

Best regards, Rainer.

Hello Rainer,

dieselschrauber wrote:

Is the engine a 2-liter 4-cylinder, right? Best regards, Rainer

Sure.

dieselschrauber wrote:

Overall, everything looks good except for the somewhat high air mass. However, I think that >1400mg/H at 4000rpm seems a bit too high for a 500cc single cylinder engine with 2500mbar of boost pressure. Given that BMW also relies on water cooling, I would have expected a value of around 1200mg/H. Simple leak in the charge air ducts or the intercooler? Best regards, Rainer

Okay, so you mean that pressure is being lost, and the turbocharger is compensating by increasing its speed, which in turn increases the amount of air being drawn in.

While that would be a problem in itself, is it capable of explaining underperformance?

The boost pressure is being maintained according to the target value. I was actually surprised that the 2 bar of boost pressure wasn't sustained up to around 4000 RPM. However, the fuel injection amount seems to be okay. Therefore, in my opinion, the performance should also be acceptable.

Am I making a mistake in my thinking?

How exactly does the Registerturbo regulate boost pressure? The swirl flaps only distribute the air between the large and small turbochargers. Is there still a wastegate like in the past?

Sure, here's the translation:

"Thank you in advance."

LG,

Bo.

Bo Duke wrote:

Okay, so you mean that pressure is being lost, and the turbocharger is compensating by increasing its speed, which in turn increases the amount of air being drawn in. While that would be a problem in itself, is it capable of explaining underperformance? Bo

.

Well, since a "more aggressive" control of the turbocharger also increases the back pressure, as the excess air has to be drawn in and compressed, and the turbocharger itself is an obstacle in the exhaust system, it would already explain a slight decrease in power. How much would be conceivable?

LG,

Bo.

Hello,

Quote:

That would be a problem in itself; but is it capable of explaining underperformance?

Yes, in order to achieve boost pressure even with a leak, the variable turbine geometry (VTG) must close, or the wastegate must remain closed.
As a result, the exhaust back pressure increases significantly, while the actual air mass flow rate in the engine decreases, causing the engine to operate at an unfavorable air-fuel ratio.
"Substances like Russ etc. are not filtered by the DPF, but the DPF itself can quickly become full."
Since the mass airflow sensor (MAF) measures all the air being drawn in, it also detects the air that is being lost through the leak but is not available for combustion, which would explain the relatively high readings.

That can easily result in a loss of 20-30 horsepower.

I cannot provide further details regarding the specifics of your engine's turbocharging system. However, the scenario I mentioned above is a general problem that is independent of the specific technical implementation of the turbocharging.

Best regards, Rainer.

dieselschrauber wrote:

As a result, the exhaust back pressure increases significantly, while the actual air mass flow rate in the engine decreases, causing the engine to operate at an unfavorable air-fuel ratio. "Substances like Russ etc. are not filtered by the DPF, but the DPF itself can quickly become full." Since the mass airflow sensor (MAF) measures all the air being drawn in, it also detects the air that is being lost through the leak but is not available for combustion, which would explain the relatively high readings. Best regards, Rainer

Thank you for the detailed explanation. I also figured out the first part myself (see above).

I would have thought that if the boost pressure is still achieved, then everything is fine in that regard; there would be enough air available.

BUT: Due to the high compression ratio, the intake air temperature will definitely increase, which reduces the air density. At the same time, the mass airflow sensor (MAF) is essentially "fooling" the engine control unit (ECU) into thinking that there is plenty of air available. This would result in a poorer lambda value. I believe this is even measured in BMWs. Quite a few things are measured around the particulate filter...

Should I start logging the intake air temperature and, if I find it necessary, the lambda value now?
If the Lambda value is measured and is less than 1, an error should actually be reported.

I read that a significantly excessive amount of measured air mass can also lead to an error being logged in BMW vehicles. However, I don't know what constitutes "too much" or which specific vehicle models this applies to. That's the type of thing that matters.

I don't know exactly how yet, but I probably need to have the intercooler system checked (or cleaned). Besides my main job, part-time job, and home renovation, I definitely won't be able to handle it all on my own.

LG,

Bo.

Hello,

Quote:

so, should I log that Lambda?

if it is, for example, measured using a broadband lambda sensor in the DPF, then yes; but if only a "calculated" value is output, it is more likely to be useless.

Best regards, Rainer.

[quote="Bo Duke"]

dieselschrauber wrote:

As a result, the exhaust back pressure increases significantly, while the actual air mass flow rate in the engine decreases, causing the engine to operate at an unfavorable air-fuel ratio. "Substances like Russ etc. are not filtered by the DPF, but the DPF itself can quickly become full." Best regards, Rainer

Bo Duke wrote:

Should I start logging the intake air temperature and, if I find it necessary, the lambda value now? If the Lambda value is measured and is less than 1, an error should actually be reported. LG, Bo

.

Hi,

The Lambda value during acceleration is always greater than 1, ranging from 1500 to 4800.
However, the value is likely calculated; in any case, I haven't found any values for the sensor's voltage, as is the case with most other sensors.

The particulate filter regenerates approximately every 500 km, which is apparently normal.

Intake air temperature during full throttle in 4th gear, increasing from approximately 5 K to +50 K (approximately 70°C absolute). That's (significantly) higher than it was back then with the ARL and tuning..., as far as I remember.

However, the initial visual inspection of the charge air cooler system revealed no obvious issues.

Can anyone provide any information about target values? Oh man, it was easier with the VW .

Hello,

Well, as I said, the air mass is unusually high, and an increased intake air temperature would also indicate a leak. I'm not sure what "normal" LLT (Longitudinal Load Test) values are for that BMW engine.

Do you have the option to check a comparable vehicle?

Best regards, Rainer.

dieselschrauber wrote:

Hello, Quote: so, should I log that Lambda? if it is, for example, measured using a broadband lambda sensor in the DPF, then yes; but if only a "calculated" value is output, it is more likely to be useless. Best regards, Rainer;-) The lambda value seems to be coming from a sensor; a voltage value is being displayed.

Do you have the option to check a comparable vehicle?

Best regards, Rainer.

dieselschrauber wrote:

I'm going to start looking for it...

I can't post in the upload section because of this message: "Only users with special permissions (e.g., members of the 'Blaumänner' group, or those with a licensed or support key) have the permission to create posts in this forum." Therefore, I'm posting here instead.

It is noticeable:

The reference vehicle (manufactured in May 2010) has more power.

Boost pressure build-up and fuel injection increase are slightly delayed (as of 09/2007).

The air mass is quite high in both vehicles, exceeding 1,400 mg/H at 4000 RPM.

In the older model (manufactured in 09/2007), the air volume under the small loader is generally higher than in the newer model.

May I still assume that the values do not indicate an intercooler leak?

In the 05/2010 model, the fuel injection is reduced much less compared to the older 09/2007 model. The newer model easily revs past 5000 RPM in third gear. In the older model, reaching 5000 RPM in third gear is not possible. The fuel injection is abruptly reduced at approximately 4700 RPM, creating a sensation similar to a gasoline engine's rev limiter. This is supposedly also the reason why the top speed cannot be reached in the older model; it would require 4800 RPM in sixth gear. The 1er Forum can be explored extensively.

P.S.: K-Power is a super cool tool!!!

LG,

Bo.