Air Flow Meter/Sensor: Testing and Inspection

1. Disconnect battery ground cable.
2. Remove lefthand speaker cover from instrument panel, then speaker.
3. Remove ECM and bracket, then fuse panel and relays from steering column retainer.

Fig. 66 Testing AFS Circuit:

4. Connect ECM to wiring harness, then voltmeter between ``+B'' terminal and ground of AFS connector as shown in Fig. 66.
5. Turn the ignition switch to the On position, engine Off.
6. Voltage reading should be the same as battery voltage. If voltage reading is not as specified, check electrical connectors for poor connections and/or open or short to ground in wiring harness.
7. Turn the ignition switch to the Off position, then connect AFS connector to air flow sensor.

Fig. 67 Testing ECM & AFS Wiring Circuit:

8. Connect voltmeter as shown in Fig. 67, then turn the ignition switch to the On position.
9. Voltage reading should be between 1.0--1.6 volts.
10. Start the engine, voltage reading should lower than 5 volts. Voltage should rise as engine speed rises. Reference data: 1.7--2.0 volts at idle.
11. If reading are not as specified, replace AFS and/or ECM components and recheck.