DTC    P0171    System Too Lean (Bank 1)

DESCRIPTION

MONITOR DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

CONFIRMATION DRIVING PATTERN

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0171 OR P0172)

CHECK PCV HOSE CONNECTIONS

CHECK INTAKE SYSTEM

PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE INJECTION VOLUME)

READ VALUE USING INTELLIGENT TESTER (COOLANT TEMP)

READ VALUE USING INTELLIGENT TESTER (MAF)

CHECK FUEL PRESSURE

CHECK FOR EXHAUST GAS LEAK

CHECK FOR SPARKS AND IGNITION

INSPECT FUEL INJECTOR ASSEMBLY (INJECTION AND VOLUME)

INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)

CHECK TERMINAL VOLTAGE (+B OF AIR FUEL RATIO SENSOR)

CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)

REPLACE AIR FUEL RATIO SENSOR

PERFORM CONFIRMATION DRIVING PATTERN

PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE EGR STEP POSITION)

INSPECT EGR VALVE ASSEMBLY

CHECK HARNESS AND CONNECTOR

CHECK WHETHER DTC OUTPUT RECURS

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM)

REPLACE MASS AIR FLOW METER SUB-ASSEMBLY

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED