Discussion and questions related to the course EFI Tuning Fundamentals
Is the MAF measurement displayed in OBDII as gm/s the total mass flow or the calculated single cylinder mass flow.
I calculated the mass flow for EJ25 @ 800 rpm (assuming 100%VE) to be approx 20gm/s
Since most 4 cylinder engines are at closer to 4 or 5 gm/s @ idle in OBDII data; does this mean OBDII displays single cylinder values or have I gone wrong in my math?
How did you calculate that the engine mass flow at 800 RPM was 20 gm/s?
What engine has a 100%VE at 800 RPM while idling?
Did you consider that only one half the displacement moves every revolution on a four stroke engine?
What Manifold Pressure did you assume for the idle condition?
Which exact OBD2 PID are you referencing? 0x10 (16 decimal)?
According to https://en.wikipedia.org/wiki/OBD-II_PIDs that is the sensor value, so I would think it was the total mass flow rate.