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Phil --

Maybe I misunderstood what you're proposing..... but substituting a fixed resistor for the hot wire in the AMM won't really work.

The air mass meter is a device called a "hot wire anemometer" (an anemometer is another name for a wind-speed measuring device). In this case, the wire is heated a fixed amount, and the temperature of the wire is measured. The temperature is closely tied to the air velocity past the wire.

(Fixed heating is accomplished by running a fixed current through the wire, and the temperature is inferred by measuring the resistance, which is measured by the resulting voltage drop across the wire.)

You could substitute a resistor for the wire, but the time response of the device would be many seconds -- perhaps minutes -- and your FI system needs millisecond response. The only way to achieve that is with a very low-mass resistor -- hence, the fine wire.

The reason the FI control system goes through the "burn-off" cycle at shutdown is the keep the wire clean -- any carbon, soot, or dust adds insulation (which means errors) and adds to the mass (which means slower response time).