Operation CHARM: Car repair manuals for everyone.

Air Flow Meter/Sensor

MASS AIR FLOW SENSOR

Description
The Mass Air Flow Sensor installed between the air cleaner assembly and the throttle body (inserted the intake air hose). The type of mass air flow sensor is a hot wire and composed of a hybrid circuit, hot wire element (sensor ring) which made of a platinum wire, housing, protective grid, moulding ring. Mass air flow rate is measured by detection of heat transfer from a hot wire probe and the change of the mass air flow rate causes change in the amount of heat being transferred from the hot wire probe surface to the air flow. This results in the change of the temperature of the hot wire probe and in the change of "Resistance".





Circuit Diagram





Troubleshooting Procedures





Using Scan Tool





Using Voltmeter

NOTE: When the vehicle is new (within initial operation of about 300 miles), the mass air flow sensor air quantity may be about 10% higher.

















Harness Inspection Procedure