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Re: MAF BLM based tuning
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/