Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Air Flow Meter/Sensor: Testing and Inspection

Component Inspection

MASS AIR FLOW SENSOR
1. Reconnect harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.







3. Check voltage between ECM terminal 72 (Mass air flow sensor signal) and ground.
4. If the voltage is out of specification, proceed the following.
a. Turn ignition switch "OFF".
b. Disconnect mass air flow sensor harness connector and reconnect it again.
c. Perform steps 2 and 3 again.
5. If NG, remove mass air flow sensor from air duct. Check hot film for damage or dust.
6. If NG, clean or replace mass air flow sensor.