IAT equipped MAF at Type1/2 boards (not equipped)

[midian]

I think this question was asked numerous times, but I searched many times here, or at other sourses and hadn't get an answer.

Older MAFs (hot wire usually) had only one output - signal (they had temp sensor integrated, but there were no output).
Some of descriptions shows it as "additional" temp sensor.

Long story short:
1. what is nescessity of using it?
2. will type1/2 (w/out IAT sensor MAFs ) ECUs operate normally?

[Matt]

1. Some ECUs (later model Nissans) use IAT to correct boost, timing etc based on the difference in ambient temperature temps. Where real life boost pressure changes based on air temps
2. Most Nissan ECUs run a pill type boost arrangement with upto usually max 8psi from factory so did not factor in the air temps. BNR32 GTR is the only table which used IAT for some of its tables as an extra input

[midian]

understood. thanks.