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Mass Air Flow (MAF) & Intake Air Temperature (IAT) Sensor Inspection

Mass Air Flow (MAF) & Intake Air Temperature (IAT) Sensor Inspection

CAUTION:
- When servicing MAF & IAT sensor, be sure to observe the following items.
- Do not expose MAF & IAT sensor to any shock. If it has been dropped, it should be replaced.

- Do not heat MAF & IAT sensor more than 100 °C (212 °F). Otherwise, it will be damaged.


IAT Sensor Inspection
1. Remove MAF & IAT sensor.
2. Check sensor O-ring (1) for damage and deterioration. If faulty condition is found, replace MAF & IAT sensor.
3. Measure resistance between sensor terminals "1" and "2" while blowing hot air to temperature sensing part (2) of MAF & IAT sensor (3) using hot air drier (4). If measured resistance is out of specified value, replace MAF & IAT sensor.

Intake air temperature sensor resistance
-20 °C (-4 °F): 13.6 - 18.4 k Ohms
20 °C (68 °F): 2.21 - 2.69 k Ohms
60 °C (140 °F): 0.493 - 0.667 k Ohms










MAF Sensor Inspection
1. Remove MAF & IAT sensor.
2. Connect battery (2) and voltmeter (3) to MAF & IAT sensor (1) as shown in figure.
3. Check that voltage varies depending on amount of blowing air as the following graph. If faulty condition is found, replace MAF & IAT sensor.