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Air Flow Meter/Sensor: Testing and Inspection

ON-VEHICLE INSPECTION

NOTE:
- Perform the MAF meter inspection according to the procedures.
- Only replace the MAF meter when both the LONG FT#1 value and MAF value in the DATA LIST (with the engine stopped) are not within the normal operating range.

1. INSPECT MASS AIR FLOW METER




a. Perform the confirmation driving pattern.
1. Connect the intelligent tester to the DLC3.
2. Turn the ignition switch ON.
3. Turn the intelligent tester ON.
4. Clear the DTCs.
5. Start the engine and warm it up with all accessory switches OFF (until the engine coolant temperature is 75°C (167°F) or more).
6. Drive the vehicle at 31 mph (50 km/h) or more for 3 or more *1.
7. Let the engine idle (accelerator pedal fully released) for 2 minutes or more *2.
8. Perform steps *1 and *2 at least 3 times.




b. Read the value using intelligent tester (LONG FT#1).
1. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / LONG FT#1.
2. Read the values displayed on the tester.

Standard value: With in -15 to +15%

If the result is not with in the specified range, perform the inspection.

c. Read the value using intelligent tester (MAF).

NOTE:
- Turn off the engine.
- Perform the inspection with the vehicle indoors and on a level surface.
- Perform the inspection of the MAF meter while it is installed in the air cleaner case (installed on the vehicle).
- During the test, do not use the exhaust air duct to perform suction on the exhaust pipe.

1. Turn the ignition switch to ACC.
2. Turn the ignition switch ON (do not run the engine).
3. Turn the tester ON.
4. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / MAF.
5. Wait 30 seconds, and read the values on the intelligent tester.

Standard condition: Less than 0.72 g/sec

- If the result is not as specified, replace the MAF meter.
- If the result is within the specified range, inspect the cause of the extremely rich or lean air fuel ratio.