Re: MAF BLM based tuning

[Ludis Langens <ludis@cruzers.com>]

Dave Zug wrote:
> 
> Trouble is, I don't trust the framing that comes out of the ALDL.  it almost
> seems as if there is some delay between certain data members.  If my RPM
> delta is 1000 in 3 frames, and some data is 3 frames behind, I am tweaking
> in the complete wrong area!
> 
> Are the items in the datastream prioritized? are some maybe updated every
> other pass? if so that stinks!

Most/all of the values in the ALDL stream are pulled directly from the
RAM variables used by the ECM.  Some of those contain a
filtered/averaged value which lags the true value.  Your diagnostic data
might be three frames behind - but the ECM is also working with data
"three frames behind".  This is why there are so many tables dealing
with transient conditions.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/


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