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Diagnosis & Repair

NOTE: Read freeze frame data using hand-held tester or OBD II scan tool. Because freeze frame records engine conditions when malfunction is detected, when trouble shooting it is useful for determining whether vehicle was running or stopped, engine warmed up or not, air-fuel ratio lean or rich, etc. at time of malfunction.

For wiring diagram, see DTC P0100: MASS AIR FLOW CIRCUIT MALFUNCTION . Check if DTC (besides P0101) is output. If only P0101 is output, replace intake air flow meter sub-assembly. See REMOVAL & INSTALLATION - 4-CYLINDER article. If P0101 and other codes are output, diagnose and repair those codes first. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .