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Old Jun 20, 2013 | 12:45 PM
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Does speed density use data from O2's?
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Old Jun 20, 2013 | 12:59 PM
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There is SD in OL (open loop) which doesnt use the O2's or SD in CL (closed loop) it WILL use the O2's.
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Old Jun 20, 2013 | 01:23 PM
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Originally Posted by work in progress
Does speed density use data from O2's?
Speed density basically means the airflow is being estimated from the VE table instead of measured by the MAF sensor. You can still use O2's with SD (closed-loop) or not (open-loop).

EFILive's custom operating systems have something called semi-open loop which uses the short term fuel trims only instead of a combination of the short and long term fuel trims. This is what I'm running now with SD and it works pretty well.
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Old Jun 20, 2013 | 01:47 PM
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Does speed density use data from O2's?
Speed density means a lack of MAF input, not necessarily that it will or will not use O2s.

As mentioned, open or closed loop is what differentiates between a tune using or not using the O2 sensors.
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