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In Air Flow Meter/Sensor

Air Flow Meter:






PURPOSE
Detects temperature of intake air and signals PCME to compensate air/fuel mixture as required.

LOCATION
Part of airflow sensor.

OPERATION
Sensor is a negative temperature coefficient thermistor; as temperature increases, resistance decreases. Cold air is more dense than warm air. The PCME measures sensor resistance, calculates incoming air temperature, and uses this information to regulate fuel injection quantity, idle speed control, and canister purge control. Sensor resistance is checked at airflow meter terminals "E2" and "THAa":

TEMPERATURE / RESISTANCE (K OHMS)

-4°F (-20°C) / 10K - 20K
68°F (20°C) / 2K - 3K
140°F (60°C) / 0.4K - 0.7K