Should those two values be basically the same?

Thanks,

Aaron

 

No.

RBob.

 

In most situations, they should be nearly the same neglecting scaling and resolution differences. The raw input value is the unlimited airflow expressed as an 8 bit value. If the two values differ significantly then the MAF flow value is being limited by the max maf flow vs rpm table.

This commonly occurs with ign on and engine off or during cranking, or when the MAF sensor is unplugged or failed. Can also occur if MAF calibration has been changed or if the actual airflow exceeds the max maf vs rpm table limit.

 

I guess it depends upon the definition of "MAF raw input." To me it is the 0 to 5 volt output of the MAF that is the input to the ECM.

RBob.