MAFless mapping

[Martin306]

Can you replace them with a MAP sensor?

I wondered that too. Still 0-5v output. Would be an interesting experiment.

Yes and No. pressure and air flow are completely different.

Big turbo, low pressure can shift the same air into your engine as little turbo and high pressure. so an ECU map based on a MAP would be all to hell if you changed your turbo or if boost was different (due to atmospheric changes) etc. You would have "good and bad" days, and nobody wants that

Also, unlike a petrol, there's no throttle position so the airflow can't be calculated based on pressure. Petrol uses MAP + TPS to calculate air flow and it's not accurate.

That's my understanding anyway