I have a 1998 blackbox PCM from a tahoe and im trying to figure out how to disable speed density calculations (short of just failing the map sensor which i dont want to do).
On most Gen 3 PCMs there is a setting under dyanimc airflow called "High RPM disable" where the PCM only uses filtered mass air for fueling. By setting this to a low rpm like 400 you force the PCM to run MAF only for fueling. However as with a lot of things on these blackbox PCMs this parameter isn't available so there is no way to run MAF only without failing the MAP sensor which brings on its own set of issues.
There is a High/Low RPM threshold but not sure if that will do the same thing.
Any help is appreciated