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IAT

Scan Tool Range -40°C to 151°C, -40°F to 304°F. The PCM converts the resistance of the intake air temperature sensor to degrees. The PCM uses Intake Air Temperature (IAT) to adjust fuel delivery and spark timing according to incoming air density. IAT is also compared to ECT at startup to identify cold starts for the HO2S heater and the [1][2]EVAP diagnostics.