Component Inspection (Mass Air Flow Sensor)
- CHECK MASS AIR FLOW SENSOR-I
With CONSULT
- Turn ignition switch OFF.
- Reconnect all harness connectors disconnected.
- Start engine and warm it up to normal operating temperature.
- On CONSULT screen, select "ENGINE">>"Data Monitor".
- Check "MASS AIR FLOW SENSOR (Hz)" indication as following.
Monitor item
Condition
Indication
MASS AIR FLOW SENSOR (Hz)
Ignition switch ON (Engine stopped.)
Approx. 3, 700 Hz
Idle (Engine is warmed-up to normal operating temperature.)
4, 714 - 5, 880 Hz
2, 500 rpm (Engine is warmed-up to normal operating temperature.)
6, 080 - 6, 600 Hz
Idle to about 4, 000 rpm
4, 714 - 5, 880 Hz -> Approx. 7, 200 Hz
Without CONSULT
- Turn ignition switch OFF.
- Reconnect all harness connectors disconnected.
- Start engine and warm it up to normal operating temperature.
- Check the frequency between ECM harness connector terminals under the following conditions.
ECM
Condition
Frequency
Connector
+
-
Terminal
Terminal
F78
41
[MAF sensor signal]
42
Ignition switch ON (Engine stopped.)
Approx. 3, 700 Hz
Idle (Engine is warmed-up to normal operating temperature.)
4, 714 - 5, 880 Hz
2, 500 rpm (Engine is warmed-up to normal operating temperature.)
6, 080 - 6, 600 Hz
Idle to about 4, 000 rpm
4, 714 - 5, 880 Hz -> Approx. 7, 200 Hz
Is the inspection result normal?
YES
INSPECTION END
NO
GO TO 2.
- CHECK FOR THE CAUSE OF UNEVEN AIR FLOW THROUGH MASS AIR FLOW SENSOR
- Turn ignition switch OFF.
- Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
- Crushed air ducts
- Malfunctioning seal of air cleaner element
- Uneven dirt of air cleaner element
- Intake valve deposits
- Improper specification of intake air system parts
Is the inspection result normal?
YES
GO TO 4.
NO
GO TO 3.
- CHECK MASS AIR FLOW SENSOR-II
- Repair or replace malfunctioning part.
- Start engine and warm it up to normal operating temperature.
- On CONSULT screen, select "ENGINE">>"Data Monitor".
- Check "MASS AIR FLOW SENSOR (Hz)" indication as following.
Monitor item
Condition
Indication
MASS AIR FLOW SENSOR (Hz)
Ignition switch ON (Engine stopped.)
Approx. 3, 700 Hz
Idle (Engine is warmed-up to normal operating temperature.)
4, 714 - 5, 880 Hz
2, 500 rpm (Engine is warmed-up to normal operating temperature.)
6, 080 - 6, 600 Hz
Idle to about 4, 000 rpm
4, 714 - 5, 880 Hz -> Approx. 7, 200 Hz
- Repair or replace malfunctioning part.
- Start engine and warm it up to normal operating temperature.
- Check the frequency between ECM harness connector terminals under the following conditions.
ECM
Condition
Frequency
Connector
+
-
Terminal
Terminal
F78
41
[MAF sensor signal]
42
Ignition switch ON (Engine stopped.)
Approx. 3, 700 Hz
Idle (Engine is warmed-up to normal operating temperature.)
4, 714 - 5, 880 Hz
2, 500 rpm (Engine is warmed-up to normal operating temperature.)
6, 080 - 6, 600 Hz
Idle to about 4, 000 rpm
4, 714 - 5, 880 Hz -> Approx. 7, 200 Hz
Is the inspection result normal?
YES
INSPECTION END
NO
GO TO 4.
- CHECK MASS AIR FLOW SENSOR-III
- Turn ignition switch OFF.
- Disconnect mass air flow sensor harness connector and reconnect it again.
- Start engine and warm it up to normal operating temperature.
- On CONSULT screen, select "ENGINE">>"Data Monitor".
- Check "MASS AIR FLOW SENSOR (Hz)" indication as following.
Monitor item
Condition
Indication
MASS AIR FLOW SENSOR (Hz)
Ignition switch ON (Engine stopped.)
Approx. 3, 700 Hz
Idle (Engine is warmed-up to normal operating temperature.)
4, 714 - 5, 880 Hz
2, 500 rpm (Engine is warmed-up to normal operating temperature.)
6, 080 - 6, 600 Hz
Idle to about 4, 000 rpm
4, 714 - 5, 880 Hz -> Approx. 7, 200 Hz
- Turn ignition switch OFF.
- Disconnect mass air flow sensor harness connector and reconnect it again.
- Start engine and warm it up to normal operating temperature.
- Check the frequency between ECM harness connector terminals under the following conditions.
ECM
Condition
Frequency
Connector
+
-
Terminal
Terminal
F78
41
[MAF sensor signal]
42
Ignition switch ON (Engine stopped.)
Approx. 3, 700 Hz
Idle (Engine is warmed-up to normal operating temperature.)
4, 714 - 5, 880 Hz
2, 500 rpm (Engine is warmed-up to normal operating temperature.)
6, 080 - 6, 600 Hz
Idle to about 4, 000 rpm
4, 714 - 5, 880 Hz -> Approx. 7, 200 Hz
Is the inspection result normal?
YES
INSPECTION END
NO
Clean or replace malfunctioning mass air flow sensor.