Does FAST do a barometric zeroing at key-on?

[ijames]

Subject basically says it all. I know that the GM speed density ecms take a map reading at key-on, before cranking, to compensate for atmospheric pressure changes. Does the FAST do this as well?

 

[Craig Smith]

Nope! A true speed/density system has no reason to do this. Since you are reading absolute pressure in the manifold, any changes in air density will have a direct impact on the pressure reading in the intake.