Possibly stupid question. re: EFI mods.

[Toecutter]

Okay... if a map is downloaded that "deletes" the oxygen sensors... how does the EFI adapt to changing conditions, like altitude?

[Ncdan]

Don’t fret the dumb question thingy as I hold the honor of that trophy here, on this same subject. I’ll guarantee you that before the end of this day you will have your question answered to your total understanding. There are some extremely knowledgeable guys here on this subject.

[Wayne Orwig]

There are temperature and pressure sensors, and there is a map for each of those to tweak the fuel.

[pyoungbl]

To embellish what Wayne wrote:  You have a basic map.  You also have supplemental tables that can apply corrections to the map as needed.  The temp sensor and air pressure sensor each have a table.  The O2 sensor/s also have a table for correction.  All you are doing by deleting the O2 is removing one set of adjustments + or - of the basic map.

[Ncdan]

Okay... if a map is downloaded that "deletes" the oxygen sensors... how does the EFI adapt to changing conditions, like altitude?

Told Ya Toe ;)

[usedtobefast]

One point ... a map doesn't HAVE to "delete" the sensors.  Most maps load in better values and then are set to ignore input from the sensors.  But you could put in a modified map that still uses the sensors.  An updated factory map for example, could have better fueling numbers but it still uses sensor inputs and acts accordingly.