alpha-n and fuel trimming

[shane@mbtech]

I find that the Alpha N mapping in the second stage of the fuel parameters can lock out the fuel adaptations of the standard ECU given that the parameters may have been altered to allow for the standard air mass meter to compensate for increased levels of activity in throttle during extended requiremnts of torque in the first instance

I read that in a brummie accent and knew it did not come from your brain:hahaha::blalalala:, then re read it and thought it was bullshit, so quite possibly thought up by you! LOL

[Hazy]

Hello ,

I own a normal M3 E46 with an MK airbox and an alpha-n reprogramming on the stock ECU.

Although my car is running very nice , I have been checking through the GT1 module the adaptation values and I have discovered that the dme is making NO compensation what so ever on the injection time (both additive and multiplicative adaptation values are ZERO).

I think that the MK alpha-n programming has "locked out" the fuel adaptation routines ...

my question for all the csl owners is whether this applies to the STANDARD alpha-n programming of the csl , or not ???

I mean does the csl make fuel adaptions (have you ever checked) or not ???

thanks

I find that the Alpha N mapping in the second stage of the fuel parameters can lock out the fuel adaptations of the standard ECU given that the parameters may have been altered to allow for the standard air mass meter to compensate for increased levels of activity in throttle during extended requiremnts of torque in the first instance

[cantfind1]

I can sort of understand why they've turned the trimming off - if you don't then over time the car basically 'reverts' back to stock tune, negating any benefits gained from Alpha N - the stock DME is designed that way for longevity.

Yep got it in one!

CSL MSS54HP ecu uses a completely different mapping software to the standard MSS54 ecu as well, there are many more maps, most of them not understood! Remapping a CSL is completely different to Remapping a standard M3.

CSL's will have adaptation values. Short and long term.

Normally in "alpha-n" tuned standard M3's the short term adaptive values are turned off, the long term still remain, for the reason stated by NZ_M3.

[shimmy]

I kept revving it to 8400 !!!:hahaha::smokin:

Couldnt resist that one !! spun a shell really ... very rare on S54 it would appear, engine was delimited ....even if driver was limited !:whistle:

Yes very rare.........very.:smokin:

[DuncanR]

hehehehe ... what happened ????

I kept revving it to 8400 !!!:hahaha::smokin:

























Couldnt resist that one !! spun a shell really ... very rare on S54 it would appear, engine was delimited ....even if driver was limited !:whistle:

[EVANGELOS]

Well I managed to blow an S54 engine up without all that pissing about ! ... :thumbs::hahaha: .... easy when you know how !:whistle:

hehehehe ... what happened ????

[Bounce]

Well I managed to blow an S54 engine up without all that pissing about ! ... :thumbs::hahaha: .... easy when you know how !:whistle:

:hahaha::hahaha:

[DuncanR]

Well I managed to blow an S54 engine up without all that pissing about ! ... :thumbs::hahaha: .... easy when you know how !:whistle:

[shane@mbtech]

The knock sensors are working ... and the dme adapts the ignition timing ... however IF a lean afr occurs I don't think that any adaptation on the timing would change anything !!!

~It might change it, but it might be too late.

[EVANGELOS]

The knock sensors should theoratically come into play in a lean situation and knock back timing - so personally I wouldn't worry about it too much tbh (unless they've turned that off too? Possible if they are using the limp home map as the main mapping .. which would be stupid actually)...

The knock sensors are working ... and the dme adapts the ignition timing ... however IF a lean afr occurs I don't think that any adaptation on the timing would change anything !!!

[NZ_M3]

Now since we are on the subject ... my opinion is that all "aplha-n" programmers that "bypass" the fuel adaptation routine (e.g AA or mine) do it so as to retain a given a/f ratio without having the ecu messing about ...

the main problem with "regular" M3's and maff-less proframming is that the dme takes into account on the fuel trimming adaption routine both the 02 sensors AND the maf ... so when u take out the maf it is probable that there is going to be a problem if u allow the dme to adapt ...

The knock sensors should theoratically come into play in a lean situation and knock back timing - so personally I wouldn't worry about it too much tbh (unless they've turned that off too? Possible if they are using the limp home map as the main mapping .. which would be stupid actually).

I can sort of understand why they've turned the trimming off - if you don't then over time the car basically 'reverts' back to stock tune, negating any benefits gained from Alpha N - the stock DME is designed that way for longevity.

[alexk]

NZ_M3 hit the nail in head again :beer:

[EVANGELOS]

Hi,

Evangelos- ...

You also say yours are ''locked out'' but
that your Car is running ''really well''.

So why do you want to re-configure something that
is as you have said, running really well ? ...

Well I don't want to change anything but I was curious whether the csl does fuel trimming or not ...

On the other hand I must confess that I feel a little worried about my dme making NO fuel trimming what so ever ... since this means that IF an injector or anything else on the fuel trail goes wrong there is no fail safe to keep the engine from running too lean ...

Sorry took me a while to get photographic proof to answer this question.

As for your question - easy answer - yes the CSL does make fuel adaption (trimming) in both additive and multiplicative: see photo below for proof (from my CSL). Hope this helps:...

Thanks man ... it is exactly what I asked for ...


Now since we are on the subject ... my opinion is that all "aplha-n" programmers that "bypass" the fuel adaptation routine (e.g AA or mine) do it so as to retain a given a/f ratio without having the ecu messing about ...

the main problem with "regular" M3's and maff-less proframming is that the dme takes into account on the fuel trimming adaption routine both the 02 sensors AND the maf ... so when u take out the maf it is probable that there is going to be a problem if u allow the dme to adapt ...

so they just bypass the fuel trimming ...

not the best of ideas but still u get a steady performance as long as the injectors , fuel pump etc are in perfect working condition

[shimmy]

Cheers lads:thumbs:

It's so much clearer now! :hahaha::hahaha::hahaha:

T$

Thicko!

Surely now you know what it is all about!
:whistle:

[glendog74]

Cheers lads:thumbs:

It's so much clearer now! :hahaha::hahaha::hahaha:

T$

+1 :hahaha: :hahaha: :hahaha:

My head hurts :bigcry: