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MAP = Manifold absolute pressure and is a sensor to measure vacuum, the computer calculates the engine air flow based on the vacuum, throttle position, and intake air temperature. The computer also measures the barometric pressure using the MAP sensor before the engine cranks, this lets the computer compensate for altitude, or how dense the air is. Typical ...


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Also, remember that MAF is a reading of the amount of air entering the engine. If you have a backflow issues (high backpressure) or even a timing issue where the valves are not opening and closing at the correct time (slack chains, jumped timing), your MAF sensor readings will reflect this as well. I know this post is late, but any who are looking into this ...


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This is the calculation you're looking for. IMAP = RPM * MAP / IAT MAF = (IMAP/120)(VE/100)(ED)*(MM)/(R) Where manifold absolute pressure (MAP) is in kPa, intake air temp (IAT) is in degrees Kelvin, R is 8.314 J/°K/mole and the average molecular mass of air (MM) is 28.97 g/mole. Note that, in the above formula, the volumetric efficiency of the (4-cycle!) ...


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Do you have a source for that formula? Is it possible that you are reading Calculated engine load value, which would indeed be zero when you are in neutral? Range: 0 to 100 Units: % Formula: A*100/255 I did find this page which defines it as: Calculated Load Value -- Indicates a percentage of peak available torque. Reaches 100% at wide open ...


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Yes, provided the following conditions are met: the units for the values MAF and fuel flow values are consistent. if you're using OBD-II parameters the values are usually in different units. In fact, fuel flow is usually volumetric (L/hr) and not mass flow like the reading from the MAF so you would have to correct for that by injector flow rate, I'm ...


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There is no one-size-fits-all formula Perhaps an analogy can help explain why this is. The volumetric efficiency of an engine is analogous to a person's ability to fill their lungs with air. To continue with the analogy, the various OBDII parameters are like a person's vital signs, such as heart rate, blood pressure and O2 saturation. To say that the ...



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