NefMoto

Hi guys!
Please help me with some advice:
1. the maf sensor is the same for 1.8t aum/auq/bam like rs4 and only the case diammeter is different 76mm bam case vs 83mm rs4 case?
2. MLHFM map for rs4 looks different than my values witch i adjust with nefmoto tool from 76 to 83mm. I attached comparation file. I think if the sensor is not the same the difference is normal.
Thanks in advance!

take your sensor element out of the bam maf housing, install it in the rs4 housing and use mlhfm from the rs4 file.

Thanks Marty. If i make a conclusion of your words result the rs4 maf sensor is the same as BAm/AUM/AUQ sensor and only the case diammeter is different.
But i think they are different sensors. Armagedon said too "S4 maf sensor is not the same as RS4" and i think BAM different too, so they have other voltage calculation. In this case if the sensor are different i can not use rs4 mlhfm table. Correct?
Thanks in advance!

You should not be randomly picking MAF sensors. Use the P/N (not engine code) to inform what MLHFM table to use.

Thanks again Nyet.
I use OEM maf sensor for 1.8t AUM / AUQ / BAM engines code PBT-GF30 , f0002g2049 in RS4 case.
I don't know what sensor RS4 use (find only oem part no 0 986 280 219). S4 and RS4 from 2.0 to 4.2 use the same case 83mm and the same sensor?
I generated my MLHFM with tool "mafadjust" from nefmoto. Car works ok but the difference of my generated MLHFM and RS4 (vag_me7_rs4_audi_27T file found on nefmoto) is huge. Per example at 4.99V my value is 1625 and in rs4 map is 1996

https://s4wiki.com/wiki/Mass_air_flow

2.7t RS4 uses the same bosch sensor as S4s, though there are hitachi sensor S4s as well.

Housing diameters are, of course, different.

Pretty much all bosch hfm5 sensors should be same. pbt means buthene thermoplastic and gf30 is glass fiber reinforced 30% F00Cxxxxx is the internal p/n for the maf sensor.

1,8T cars is kind like:

Wideband ECU's have final 049 inside
Narrowband ECU's have final 040 inside

Using an 049 sensor with MLHFM for 040 will make Reading about 9% lower in g/s.

For 2,7 engines cant confirm this.

For NA engines like VR6 the final is 032 and has an NTC for IAT...and a diferent MLHFM

Thanks to all.
So is good to leave my OEM sensor from wideband 1.8t xxxx049 in the 83mmcase with my calibration started from 1.8t BAM MLHFM table and adjusted with "mafadjuster" tool , or copy rs4 mlhfm from rs4?
I told you is a big differente of air flow.
I understood is other sensor on rs4 and it has other calibration.
In attached picture green is rs4 , yelow is 1.8t , red is the difference between 1.8t and rs4.
Thanks again.

Hi
Is it normal to have big difference between msdk_w (MassAirFlowAtThrottlePlate) and  mshfm_w   (MassAirFlow)
Another question is about my log i saw in ecuxplot per example at 825gr/s correspond 4.2V but in my MLHFM i have 825 aproximatly at 4.0V , another huge difference.

fogot to load the log

MLOFS. Compare at the same voltage, not the same g/sec

Thanks Nyet,
I will try to understand,
Other issues i saw in my log:
1. i have 850-870 hifgest maf value kg/h but in my file the mlmax is set to 680. the error not appear because mkmax+mlofs - 880 > my highest maf value?
2. MassAirFlowAtThrottlePlate( msdk_w ) is lower than MassAirFlow( mshfm_w ) , when rpm increased the difference increased too (higher). This means i have a boost leak or the turbo restrict the debit of air?
Thanks in advance.

Incorrect. RS4 uses a different, wider band sensor element! It's not only a housing size change.
BAM also uses this wider band sensor element IIRC.

Thanks prj. I changed in my file only mlhfm (generated with mafadjuster tool from nefmoto0 because i keep the BAM sensor ,  so the conclusion is i can not copy MLHFM from rs4 file, RIGHT?

Rewrite my issues (maybe someone not read upstairs):

1. i have 850-870 highest maf value kg/h in the log but in my file the mlmax is set to 680. the error not appear because mkmax+mlofs = 880 > my highest maf value?
2. MassAirFlowAtThrottlePlate( msdk_w ) is lower than MassAirFlow( mshfm_w ) , when rpm increased the difference increased too (higher). This means i have a boost leak or the turbo restrict the debit of air?
Thanks in advance.

do you know the pn? I have 078 906 461B for bosch s4

unfortunately the unit p/n wont tell the sensor p/n (f00xxx..) , and since vag p/n change with even the slightest iteration it could be different. But this time its whole different group of p/n.

rs4 bosch - 077133471K(X)



AFAIK, all the maf related maps in a system with mlofs active mafs take the offset in account in the values

guys , please the conclusion for me , can i use MLHFM from rs4 file with my bam sensor and rs4 case
("RS4 stock MLHFM ends at 1996.1 kg/hr. With MLOFS, that is 1796.1, or 498.9 g/sec") or it is ok how i proceed to adjust my mlhfm with mafadjuster tool witch result a different mlhfm like rs

and again please rewrite my issues from today log:
1. i have 850-870 highest maf value kg/h in the log but in my file the mlmax is set to 680. the error not appear because mkmax+mlofs = 880 > my highest maf value?
2. MassAirFlowAtThrottlePlate( msdk_w ) is lower than MassAirFlow( mshfm_w ) , when rpm increased the difference increased too (higher). This means i have a boost leak or the turbo restrict the debit of air?
Thanks in advance.

Not sure what you mean by this.

MLHFM output is not the same as the input to any MAF related table that has MAF as an input. MLOFS is added first.

thats exactly what I meant

No, in this context blazius is correct. MLMAX is vs the real value which is MLHFM + MLOFS.

Please, in the future, just look at the FR, it is much easier. No clue why you aren't getting a DTC


boost leaks are much more apparent by looking at fuel trims, since msdk_w is modeled.

That said, if fuel trims are ok but you suspect a DV leak, it may show up in ps_w vs pvdks and msdk vs mshfm

i don't logged  ps_w, will make.
from 1 week i checked and rechecked and rechecked all possible leak in the system
i don't find any problem.
so from where is the difference betwen air flow at throtle and maf? can be a bad maf sensor?
my fuel trims are instable but i have a topic on this problem, i think my injectors or fpr are bad. in 2 days will change the fpr with new 4bar fpr (now it has 3bar) and will see
i tried different TVUB but with little modification in tvub the checkengine is light.
i tried with little more fkkvs on low rpm but the same problem checkengine is light.

There is nothing to check or re-check.
You make a pressure tester and do a pressure test from turbo inlet (or on the 1.8T transverse platform from the charge pipe).
If it holds pressure -> no leak.