NefMoto

A Seat Ibiza 180hp that I have tuned months ago, BBU engine, returned to me yesterday with a lot of problem. The most noticeable is that it jerks a lot at part throttle, and the STFT is very unstable.
The owner said me that he have changed the MAF, so I have the doubt that he have put the wrong MAF.
This actual MAF on the housing have this # : 0280218032
Inside have this # : F00C 2G2 040.

The inside sensor is of a TT225 (BAM?), is the housing the right one for the sensor?

I think that if it's confirmed to be a 225 MAF I can copy MLHFM from a 225 map. I have also to copy KFKHFM?

unplug the maf, then see if it runs better.

did the owner replace with a used MAF sensor?  why is it not same as original?

It's a brand new bosch.
The story is that prior of this maf there is another one put in by an official dealer some years ago. Two weeks ago a mechanic diagnose him a bad MAF, but told him that the MAF he had was also the WRONG one! So put this F00C 2G2 040 - 0280218032 housing.
The owner can't tell me WHEN the car start to go like crap, so I'm not certain to point the finger on the maf.
And I have NO IDEA of what is the original MAF and housing # because to many MAF swap were done... >:(

The original MAF linearization ( http://nefariousmotorsports.com/forum/index.php/topic,1202.0title,.html ) peak at 1005.6 Kg/h, same as AUQ.
A 225 BAM MAF linearization peak at 1253.3 Kg/h

vag #s of the mafs in question.. might be of help..

06A906461L - AUQ, AUM

06A906461M - BAM


The BAM sensor is originally fitted in a larger housing that pysically wont fit in your oem airbox without modification, fitting it to a smaller housing(in the size you originally had), and then fetching the linearization from a BAM file will get you into even more trouble..
best would be to find the right maf AND housing, mate them and use the stock calibration.. =)

The housing that is on the car is the small one, 68mm external diameter.
So I have a 225 MAF into a 180 housing? Or there's a possibility that it's the correct configuration?

Define the hardware 100% before you go near firmware!

You could easily lose a weeks work before you find some component wasn't stock as you assumed (or were told).

The hardware was defined from the first post....but I really don't know if they are stock components or not  :-\

68mm (external measure) housing #0280 218 032
MAF element #F00C 2G2 040.

The OEM linearization in the map is the same as other 180hp engine, as the AUQ.

I am so glad I don't do this for a living. It's hard enough nailing your own problems.

This guy http://www.audifreaks.com/forums/showthread.php?t=705 found the same sensoir inside a 180 and 225 MAF housing, so there is the possibility that this MAF is stock...

the housing you have can be found in:

Audi TT Mk1 1.8T 180HP
Audi A4 B5 1.8T
Volkswagen Golf Mk4 1.8T
Volkswagen Jetta Mk4 1.8T
Volkswagen Passat B5 1.8T
also some seats/skodas.
 
and it should house this sensor: F 00C 2G2 040


these sensors are used on cars 99-01 without wideband o2 if i remember correctly.. and the F 00C 2G2 049 on the 180hp WITH wideband o2.. also a new/other housing, 06A906461L(0280 218 064), which straightens the flow a bit more for better accuracy.

so.. i think you have the right sensor fitted to the right housing.. and unless your car have wideband o2, you should have the correct MAF for that car.. now what makes me uncertain is that its a 180hp engine, and you compare it to AUQ, which IS equipped with wideband.. so.. perhaps someone tried to replace it with a non-wideband sensor, which resulted in the behavior you are seing now..?
you mention you have the same scaling as an AUQ 180hp.. BUT..
scaling on "non-wideband" vs "wideband" MAFs are different.. trying to run a non-wideband instead of the original sensor will definetly cause problems.

This car HAS a wideband!!! Is a 1.8T cupra MY 2005, BBU engine. I confirm, same linearization (MLHFM) of AUQ engine! But different KFKHFM...

So, for this car the correct MAF sensor is F 00C 2G2 049?

Maybe I can try to put the linearization of a NON wideband 180hp, so this poor guy don't have to spend other money on a MAF...

yes, if it has wideband, then it should use the 06A906461L, which is equipped with the 049 sensor.

your housing and sensor is from an older car without wideband.. and one solution could be to put the linearization from an older 150/180hk non-wideband engine in there.. just as you suggested.

my audi a3 1.8tq 150hp -00 with AQA engine uses this older MAF you have in the car now, for one, but im sure you can fetch the values from another bin-file.. i dont think it matters if it is 180 or 150hp, as long as it uses the same MAF..
engine codes: AQA, AWW, AWD, AYP, APU, AWC, ARZ, AQX, AJQ, APP.. and certainly many more 99-01 ones..

ive included a bin from my aqa box, using this maf, alltho it is not complete since the program wouldnt read past 60%.. but perhaps you can source the linearization from it, if you havent allready got a better suited bin specified.

Thanks mate, I have searched a TT 180 AJQ file, and compared the MAF linearization!!!

(http://img12.imageshack.us/img12/4779/mafs.png)

BLU is "wideband" linearization, RED "no wideband".
I'll try this afternoon the new linearization. I'm unsure to copy also KFKHFM.

Kfkhfm is tied to the intake tract. If you changed your tract, then you'll have to tune said map, if not, you shouldn't have to touch it.

Yes, I know it, however I think that a big change in MAF linearization can influence a little also the MAF correction.

actually, the 06A906461L housing have a straightener/net even after the sensor.. which might/will affect how the air moves down the intake tract.. thus the kfkhfm would need to be changed even tho the diameter of the housing or the tract itself havent been altered.. so I personally would copy even the kfkhfm.. anyway, keep us updated, this is interesting stuff.. and could save ppl some time/money if they have problems with a bad maf =)

Sorry, I reread the post. I was thinking he was using stock sensor/housing/tract for that car. My bad. What you say makes sense. I guess try it, see what your fuel trims look like.

Ok, I have copied only the linearization, and 90% of the problems gone.
I'll update tomorrow, after further test.

I think that older non wideands 1.8t have different plug for the maf sensor. I also think that the "small" 180ps sensors are different in the onoard temperature sensor they have, and to the external case. The element should be the same. Correct me if i am wrong.

I can confirm that copying the linearization work well. Howeverm this car isn't a good test bench because when I made the previous tune for 440cc injectors the car isn't in good working order. After the MAF linearization paste I have to correct KRKTE and TVUB, but I have also repaired three boost leak so....

KRKTE and TVUB have nothing to do with maf scaling.

If the car is turbo the onboard temp sensor, even if implemented, isn't used. NA cars need temp compensation, turbo cars do to, but air gets compressed/heated so its pointless. So I've been told; someone correct/school me if I'm wrong.

I don't think you are right in this because all the cars have iat sensor regardless of maf ut the internal temp sensor that mafs have are for correcting their signal output as a raw value.

I've been meaning to get back to this thread for a while, just have'nt had the time. You will see in the pictures below that the 2 turbo applications do not have the temperature sensor, while the NA V8 does. Unless I'm missing something, I believe turbo cars don't have/need them? Again, school/teach me if I'm wrong..... it's still a very strong possibility! ;D          



***** Pictures were taken by member mmmboost *****

nice picture  :)

it is true that you would need a sensor with much greater "range" on a turbo car since it compresses the air and therefore it will reach much higher temperatures, also it would need to be placed in the intake manifold.. after the air has been compressed, and after intercooler, thats why it has the external IAT.
(if you know the flow and the IAT, your ecu can calculate the density of the air entering the engine)

..but the integrated sensor is great for NA cars since u dont have to use another iat sensor in that setup.. id imagine this same sensor could be used in a blow thru maf turbo setup.. if the maf were to be placed after the ic.. :)