CHECK MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR.

1) Start the engine and warm-up engine until coolant temperature is higher than 60°C (140°F).

2) Place the shift lever in neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Open the front hood.

6) Measure the ambient temperature.

7) Read the data of mass air flow and intake air temperature sensor signal using Subaru Select Monitor or general scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedure, refer to “READ CURRENT DATA FOR ENGINE”.

• General scan tool

For detailed operation procedure, refer to the general scan tool operation manual.

QUESTION

Subtract the ambient temperature from intake air temperature. Is the obtained value −10 — 50°C (−18 — 90°F)?

Yes No

Replace the ECM.

Check the mass air flow and intake air temperature sensor.