LMM von DC: Problemlöser in allen Lebenslagen? | Posts 9+

WarLord wrote:

According to what I have read so far, the LMM (Mass Air Flow sensor) works without problems on 1.9 TDI engines, and according to VAG Com, it shows the same values as the original LMM from VW/Bosch. However, it is said not to work with the 2.5 TDI engine.

Hi.

I once copied a picture from another forum.
The comparison (using VAGCOM data logging) refers to a 150 hp TDI engine, which already has the highest airflow rate of all (standard) 1.9 engines and is therefore most similar to the DC donor engine.

And I already have the Pieburg in it. *g* By the way: You wrote that you had problems with the intercooler system on your 1Z. Where exactly was the problem?

Greetings, WarLord.

In my case, it was the rubber connectors on the hoses directly above the engine block. I replaced these with reinforced rubber hoses, and it's been quiet for 4 years. Additionally, I replaced the original clamps with stainless steel hose clamps. Since then, I haven't had any more problems with boost pressure!

@ Ulf, nice graphic!

The only thing that bothers me is that it's from the 'Gute Fahrt' forum! Sometimes I get the feeling that VW employees are posting there and sabotaging all the good ideas!

In the Passat3b.de forum, a similar measurement was performed, but with the result showing less air mass being measured up to 2000 RPM, and then a slightly increased air mass reading afterwards.

Unfortunately, I can't find the thread anymore; it was a while ago though!

Regards,

Manuel.

Okay, that's fine. You've convinced me. Is there any way to adjust the measurement somehow? Maybe with resistance or something? *g* By the way, is the 150 hp TDI really just a 1.9-liter engine? Which one is it then? It must be an older model, right?

Best regards, WarLord.

Caution!

My AHF (presumably a device or system) also indicates that it works, but it doesn't. There are HFMs (High-Frequency Modules) for my engine, some with separate measurement probes, and others that are "one-piece." I have the latter type installed, which means the DC (Direct Current) measurement probe is not compatible.

Best regards, Rainer.

@rainer

'It's the same with AWX. But with my AWX, the DC-LMM fits perfectly! However, as I said, with a functioning LMM, there is subjectively better performance and lower fuel consumption compared to using the DC part.'

@Manuel Thomas

Don't worry, this post is from me; I originally posted it on vw-audi-forum.de.
posted, and I am not affiliated with Volkswagen.
My car ran significantly worse with the DC-LMM than it did with the original one.
Below approximately 2000 RPM, there is very little power output, but then there's a sudden surge of power that occurs because, from that point on, the power output becomes relatively normal.

Rainer K. wrote:

I have HFMs for my engine, some with a separate measuring insert, and others that are "one-piece".

In my case, the latter type is installed, which means the DC measuring insert is not compatible. }
Hi Rainer,

As far as I know, the mounting dimensions of both mass airflow sensors are identical. I should compare the one from my wife's Ibiza (which has a housing) with mine (which is a Pierburg unit without a housing).

"Definitely, the connectors don't fit after the swap, but that shouldn't be an unsolvable problem..."

Hi Rainer,

As far as I know, the mounting dimensions of both mass airflow sensors are identical. I should compare the one from my wife's Ibiza (which has a housing) with mine (which is a Pierburg unit without a housing).

Of course, the plugs don't fit after the swap, but that shouldn't be an unsolvable problem.


What does the parts catalog say about this? Is there a blank pipe available as a separate part? And if so, is it still possible that the two LAMBs (lambda sensors) have significantly different characteristics, requiring a different control unit?
In the Passat B3 forum, someone once discussed this issue. However, if I remember correctly, it was due to a faulty vacuum hose.

I tested the DC LMM in my AWX. My LMM was working correctly. When the DC part was installed, the car felt slower than usual, and fuel consumption was higher! This is also confirmed by the diagram above!

@felix

You have the ARL engine with 150 hp. Does this engine use the same mass airflow sensor (MAF) as the less powerful TDIs, or is it a different variant?

Does your LMM (air mass meter) have the Bosch part number F00C 2G2 027, or the VW part number 028 906 461/06A 906 461?

I've come across your characteristic curve during my online research many times, but I never managed to find out if the ARL has the same mass flow rate. And I haven't discovered any other comparable characteristic curves yet.

Sure, no problem. Here's the translation:

'Thank you in advance.'

@felix

Then I now know where the pronounced turbo lag and the powerful kick at 2,000 revolutions per minute come from in the Mercedes CDI engine.

@joergs

It should be possible to address this with an external voltage source. Simply inject a small amount of voltage into the DC mass airflow sensor until it provides identical readings to the one from VW.

Best regards, WarLord.

The 130 hp PD engine with code AWX definitely has the same [part/component].

Bosch part number: F00C 2G2 027.

@joergs

It should be possible to address this with an external voltage source. Simply inject a small amount of voltage into the DC mass airflow sensor until it provides identical readings to the one from VW.

Greetings, WarLord.

You could also do that with your old, original one, right? Then you would save those 70 euros!

You would have to constantly readjust it because it's not particularly durable, or at least shouldn't be. The one from Pierburg is supposed to be more durable (it basically has to be, since I've never replaced it and haven't had any performance issues).

Best regards, WarLord.

You would have to constantly readjust it, as it is not particularly durable or supposed to be. The one from Pierburg is supposed to be more durable (it basically has to be, since I've never replaced it and haven't had any performance problems).

Greetings, WarLord.

um... have you already looked at yours and the one that's being referred to here???? there are actually quite a few tiny differences!!!!!

Unterschiede? Form factor?

Best regards, WarLord.