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DTC P0101: Mass Or Volume Air Flow Sensor "A" Circuit Range/Performance: Notes

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

Improper idling
Engine stall
Poor driving performance

NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .

CHECK DTC .
1. Turn the ignition switch to ON.
2. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
Is DTC other than P0101 displayed? (Current code)

Yes: Check the appropriate DTC using the "Diagnostic Trouble Code (DTC)". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

No: Go to 2.
CHECK AIR INTAKE SYSTEM .
Check the installing condition of the air intake system.

Are there holes, loose bolts or disconnection of hose on air intake system?

Yes: Repair the air intake system. Ref. to INTAKE (INDUCTION) (H4DO)>GENERAL DESCRIPTION .

No: Go to 3.
CHECK PCV HOSE .
Check the PCV hose. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DO)>PCV HOSE>INSPECTION .

Does the PCV hose have deformation, cracks or other damages?

Yes: Replace the PCV hose. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DO)>PCV HOSE .

No: Replace the mass air flow and intake air temperature sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR .