The 2S-E, 3S-FE, 3S-GE and 3S-GTE engines use an air flow meter. The 4A-FE and 5S-FE engines use a vacuum sensor. The air flow meter contains a spring-loaded measuring plate. The plate is connected to a potentiometer which controls the signal to the ECU. In this way, the control unit is advised of intake air volume and can control injector duration and ignition advance accordingly. The air flow meter and temperature sensor are tested and serviced as a single unit.
- Disconnect the air flow meter connector.
- Using a ohmmeter measure the resistance between the appropriate terminals.
- If the resistance is not as specified, replace the air flow meter. The air temperature sensor and air flow meter are replaced as a single unit.
REMOVAL & INSTALLATION
- Disconnect the negative battery terminal.
- Disconnect the air flow meter connector and the air cleaner hose.
- Remove the air cleaner cap, if equipped.
- Remove the air flow meter by prying off the lock plates, if equipped, then removing the nuts and bolt.
- Installation is the reverse of removal. Reconnect the negative battery terminal.