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Discussion Starter · #3 ·
I know it doesn't use the O2 sensor. By parameters (probably not well phrased) i meant does it use the MAF sensor and engine temp and rpms to figure out appropriate fueling or does it solely rely on rpms?
 

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I know it doesn't use the O2 sensor. By parameters (probably not well phrased) i meant does it use the MAF sensor and engine temp and rpms to figure out appropriate fueling or does it solely rely on rpms?
Why don't you think it doesn't use the O2 sensor? The O2 sensor input is omitted until it is up to temp (closed loop), but once warm, that's the ONLY way the car can tell if its running rich or lean. The car uses MANY other inputs to determine the appropriate fueling (coolant temp, MAF reading, O2mV, knock count & RPM just to name a few).
 

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Discussion Starter · #5 ·
I don't care about normal cruising or light acceleration, only full throttle open loop.

The ecu would never care what the afr is under hard acceleration (unless maybe it has a wideband, which mine does not have) because you will always want to be running rich under full throttle conditions for more power.

To be more specific, do open loop full throttle fueling calculations depend on MAF readings?
 

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Discussion Starter · #6 ·
I was able to find some more information online. I'm a noob, but from what I gather,

The computer adjusts the basic map using the O2 sensor.
This is then scaled when under Full throttle.
It looks up how long to pulse the injectors based on RPM and Load.
The Load must involve some calculation with the MAF.

Why I'm asking:

I want to make a sort of ram-air that only opens during full throttle. (I'm thinking about using a servo controlled flap on a cutup funnel into the airbox). I had read elsewhere that the fueling might only depend on RPM's, in which case forcing air in would lean it way out with a set fuel at a certain RPM.

I'm also not sure what the max amount of "load" the ecu can read or has values for, or what the maf's range is since its a N/A maf. I assume the danger would be running lean, so maybe I shouldn't attempt anything without a working wideband?
 
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