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Engine Performance DTCS

ENGINE PERFORMANCE DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

DTC Description
DTC P0101 MASS AIRFLOW (MAF) SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (HIGH INPUT) - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0102 MASS AIRFLOW (MAF) SENSOR CIRCUIT LOW INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0103 MASS AIRFLOW (MAF) SENSOR CIRCUIT HIGH INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0106 INTAKE MANIFOLD PRESSURE SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0106 INTAKE MANIFOLD PRESSURE SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0107 INTAKE MANIFOLD PRESSURE SENSOR CIRCUIT LOW INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0107 INTAKE MANIFOLD PRESSURE SENSOR CIRCUIT LOW INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0108 INTAKE MANIFOLD PRESSURE SENSOR CIRCUIT HIGH INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0108 INTAKE MANIFOLD PRESSURE SENSOR CIRCUIT HIGH INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0111 INTAKE AIR TEMPERATURE (IAT) SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0112 INTAKE AIR TEMPERATURE (IAT) SENSOR CIRCUIT LOW INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0113 INTAKE AIR TEMPERATURE (IAT) SENSOR CIRCUIT HIGH INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0116 ENGINE COOLANT TEMPERATURE (ECT) SENSOR CIRCUIT LOW INPUT
DTC P0117 ENGINE COOLANT TEMPERATURE (ECT) SENSOR CIRCUIT HIGH INPUT
DTC P0121 THROTTLE POSITION (TP) SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (HIGH INPUT)
DTC P0122 THROTTLE POSITION (TP) SENSOR CIRCUIT LOW INPUT
DTC P0123 THROTTLE POSITION (TP) SENSOR CIRCUIT HIGH INPUT
DTC P0125 ENGINE COOLANT TEMPERATURE TOO LOW FOR CLOSED LOOP FUEL CONTROL
DTC P0130 FRONT OXYGEN SENSOR (O2S) CIRCUIT MALFUNCTION - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0131 FRONT OXYGEN SENSOR (O2S) CIRCUIT RANGE/PERFORMANCE PROBLEM (LOW INPUT) - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0132 FRONT OXYGEN SENSOR (O2S) CIRCUIT RANGE/PERFORMANCE PROBLEM (HIGH INPUT) - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0133 FRONT OXYGEN SENSOR (O2S) CIRCUIT SLOW RESPONSE
DTC P0135 FRONT OXYGEN SENSOR (O2S) HEATER CIRCUIT MALFUNCTION - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0136 REAR OXYGEN SENSOR (O2S) CIRCUIT MALFUNCTION
DTC P0139 REAR OXYGEN SENSOR (O2S) CIRCUIT SLOW RESPONSE
DTC P0141 REAR OXYGEN SENSOR (O2S) HEATER CIRCUIT MALFUNCTION - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0141 REAR OXYGEN SENSOR (O2S) HEATER CIRCUIT LOW INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0170 FUEL TRIM MALFUNCTION - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0171 FUEL TRIM MALFUNCTION (TOO LEAN) - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0172 FUEL TRIM MALFUNCTION (TOO RICH) - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0181 FUEL TEMPERATURE SENSOR "A" CIRCUIT RANGE/PERFORMANCE PROBLEM
DTC P0182 FUEL TEMPERATURE SENSOR "A" CIRCUIT LOW INPUT
DTC P0183 FUEL TEMPERATURE SENSOR "A" CIRCUIT HIGH INPUT
DTC P0301 P0304: CYLINDERS NO. 1-4 MISFIRE DETECTED
DTC P0325 KNOCK SENSOR (KS) CIRCUIT MALFUNCTION
DTC P0335 CRANKSHAFT POSITION (CKP) SENSOR CIRCUIT MALFUNCTION
DTC P0336 CRANKSHAFT POSITION (CKP) SENSOR RANGE/PERFORMANCE PROBLEM
DTC P0340 CAMSHAFT POSITION (CMP) SENSOR CIRCUIT MALFUNCTION
DTC P0341 CAMSHAFT POSITION (CMP) SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM
DTC P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD
DTC P0440 EVAP SYSTEM MALFUNCTION
DTC P0443 EVAP SYSTEM PURGE CONTROL VALVE CIRCUIT LOW INPUT
DTC P0446 EVAP SYSTEM VENT CONTROL CIRCUIT LOW INPUT
DTC P0451 EVAP SYSTEM PRESSURE SENSOR RANGE/PERFORMANCE PROBLEM
DTC P0452 EVAP SYSTEM PRESSURE SENSOR LOW INPUT
DTC P0453 EVAP SYSTEM PRESSURE SENSOR HIGH INPUT
DTC P0461 FUEL LEVEL SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM
DTC P0462 FUEL LEVEL SENSOR CIRCUIT LOW INPUT
DTC P0463 FUEL LEVEL SENSOR CIRCUIT HIGH INPUT
DTC P0480 COOLING FAN RELAY NO. 1 CIRCUIT LOW INPUT
DTC P0483 COOLING FAN FUNCTION PROBLEM
DTC P0505 IDLE CONTROL SYSTEM LOW INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0506 IDLE CONTROL SYSTEM RPM LOWER THAN EXPECTED - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0506 IDLE CONTROL SYSTEM RPM LOWER THAN EXPECTED - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P0507 IDLE CONTROL SYSTEM RPM HIGHER THAN EXPECTED
DTC P0601 INTERNAL CONTROL MODULE MEMORY CHECK SUM ERROR
DTC P1100 STARTER SWITCH CIRCUIT LOW INPUT
DTC P1101 NEUTRAL POSITION SWITCH CIRCUIT HIGH INPUT (A/T)
DTC P1101 NEUTRAL POSITION SWITCH CIRCUIT LOW INPUT (M/T)
DTC P1102 PRESSURE SOURCES SWITCHING SOLENOID VALVE CIRCUIT LOW INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1103 ENGINE TORQUE CONTROL SIGNAL NO. 1 CIRCUIT MALFUNCTION
DTC P1106 ENGINE TORQUE CONTROL SIGNAL NO. 2 CIRCUIT MALFUNCTION
DTC P1110 ATMOSPHERIC PRESSURE SENSOR CIRCUIT LOW INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1111 ATMOSPHERIC PRESSURE SENSOR CIRCUIT HIGH INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1112 ATMOSPHERIC PRESSURE SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1115 ENGINE TORQUE CONTROL CUT SIGNAL CIRCUIT HIGH INPUT
DTC P1116 ENGINE TORQUE CONTROL CUT SIGNAL CIRCUIT LOW INPUT
DTC P1120 STARTER SWITCH CIRCUIT HIGH INPUT
DTC P1121 NEUTRAL POSITION SWITCH CIRCUIT LOW INPUT (A/T)
DTC P1121 NEUTRAL POSITION SWITCH CIRCUIT HIGH INPUT (M/T)
DTC P1122 PRESSURE SOURCES SWITCHING SOLENOID VALVE CIRCUIT HIGH INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1130 FRONT OXYGEN SENSOR (O2S) CIRCUIT MALFUNCTION (OPEN CIRCUIT) - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1131 FRONT OXYGEN SENSOR (O2S) CIRCUIT MALFUNCTION (SHORT CIRCUIT) - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1132 FRONT OXYGEN SENSOR (O2S) HEATER CIRCUIT LOW INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1133 FRONT OXYGEN SENSOR (O2S) HEATER CIRCUIT HIGH INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1134 FRONT OXYGEN SENSOR (O2S) MICRO-COMPUTER PROBLEM - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1139 FRONT OXYGEN SENSOR (O2S) NO. 1 HEATER CIRCUIT RANGE/PERFORMANCE PROBLEM - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1141 MASS AIRFLOW SENSOR (MAF) CIRCUIT RANGE/PERFORMANCE PROBLEM (LOW INPUT) - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1142 THROTTLE POSITION (TP) SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (LOW INPUT)
DTC P1143 INTAKE MANIFOLD PRESSURE SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (LOW INPUT) - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1144 INTAKE MANIFOLD PRESSURE SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (HIGH INPUT) - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1150 FRONT OXYGEN SENSOR (O2S) HEATER CIRCUIT HIGH INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1151 REAR OXYGEN SENSOR (O2S) HEATER CIRCUIT HIGH OUTPUT
DTC P1325 KNOCK SENSOR (KS) CIRCUIT LOW INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1400 FUEL TANK PRESSURE CONTROL SOLENOID VALVE CIRCUIT LOW INPUT
DTC P1420 FUEL TANK PRESSURE CONTROL SOLENOID VALVE CIRCUIT HIGH INPUT
DTC P1422 EVAP SYSTEM PURGE CONTROL VALVE CIRCUIT HIGH INPUT
DTC P1423 EVAP SYSTEM VENT CONTROL HIGH INPUT
DTC P1442 FUEL LEVEL SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM 2 - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1443 EVAP SYSTEM VENT CONTROL FUNCTION PROBLEM
DTC P1505 IDLE CONTROL SYSTEM CIRCUIT HIGH INPUT - IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1507 IDLE CONTROL SYSTEM MALFUNCTION (FAIL-SAFE)
DTC P1510 P1515: IDLE AIR CONTROL (IAC) SOLENOID VALVE SIGNAL No. 1-3 CIRCUITS HIGH/LOW INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1516 IDLE AIR CONTROL (IAC) SOLENOID VALVE SIGNAL NO. 4 CIRCUIT LOW INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1517 IDLE AIR CONTROL (IAC) SOLENOID VALVE SIGNAL NO. 4 CIRCUIT HIGH INPUT - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC P1520 RADIATOR FAN RELAY NO. 1 CIRCUIT HIGH INPUT
DTC P1540 VEHICLE SPEED SENSOR (VSS) MALFUNCTION 2 - EXCEPT IMPREZA & LEGACY 2.2L (CALIFORNIA EMISSIONS)
DTC 1560 BACK-UP VOLTAGE CIRCUIT MALFUNCTION