Air Flow Meter/Sensor: Testing and Inspection
MASS AIRFLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTIONNOTE: Perform the following test only when directed.
MAF Sensor Voltage Inspection
1. Turn the ignition switch to LOCK.
2. Disconnect the PCM connector.
3. Connect the SST (104 Pin Breakout Box) to the PCM connector and the PCM as shown.
4. Tighten the connector attaching bolt.
Tightening torque: 3.0 - 5.4 N.m {30 - 56 kgf.cm, 27 - 48 in.lbf}
5. Turn the ignition switch to ON.
6. Measure the voltage between the breakout box pins 36 and 88.
- If not as specified, perform the "MAF Sensor Circuit Open/Short Inspection".
Specification: 0.0 - 0.1 V
7. Turn the ignition switch to START and warm up the engine completely.
8. Measure the voltage between the breakout box pins 36 and 88.
- If not as specified, perform the "MAF Sensor Circuit Open/Short Inspection".
Specification: 0.5 - 0.8 V
MAF Sensor Circuit Open/Short Inspection
1. Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION)
2. Connect the SST (104 Pin Breakout Box) with the PCM disconnected.
3. Tighten the connector attaching bolt.
Tightening torque: 3.0 - 5.4 N.m {30 - 56 kgf.cm, 27 - 48 in.lbf}
4. Inspect the following wiring harness for open or short (Continuity check).
Open circuit
- If there is no continuity, the circuit is open. Repair or replace the harness.
- MAF/IAT sensor terminal B (harness-side) and main relay terminal C (harness-side)
- MAF/IAT sensor terminal E (harness-side) and 104 pin breakout box terminal 88
- MAF/IAT sensor terminal D (harness-side) and 104 pin breakout box terminal 36
Short circuit
- If there is continuity, the circuit is shorted. Repair or replace the harness.
- MAF/IAT sensor terminal B harness-side and body ground MAF/IAT sensor terminal E (harness-side) and power supply MAF/IAT sensor terminal E harness-side and body ground
- MAF/IAT sensor terminal D harness-side and power supply
Specification:
MAF Rate and Load Value
NOTE: The scan tool shows the MAF rate and load value.