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General Diagnostic Table: Inspection: Engine

WARNING: This page is about a different variant/trim than selected.
NOTE: Malfunction of parts other than those listed is also possible. Refer to MECHANICAL (STI)>SYMPTOMS AND CAUSES .
Symptoms Faulty parts
  1. Engine stalls during idling.
  1. Electronic throttle control
  2. Manifold absolute pressure sensor
  3. Mass air flow and intake air temperature sensor
  4. Ignition parts (1)
  5. Engine coolant temperature sensor (2)
  6. Crankshaft position sensor (3)
  7. Camshaft position sensor (3)
  8. Fuel injection parts (4)
  1. Rough idling
  1. Electronic throttle control
  2. Manifold absolute pressure sensor
  3. Mass air flow and intake air temperature sensor
  4. Engine coolant temperature sensor (*2)
  5. Ignition parts (1)
  6. Air intake system (5)
  7. Fuel injection parts (4)
  8. Crankshaft position sensor (3)
  9. Camshaft position sensor (3)
  10. Oxygen sensor
  11. Fuel pump and fuel pump relay
  1. Engine does not return to idle.
  1. Electronic throttle control
  2. Engine coolant temperature sensor
  3. Manifold absolute pressure sensor
  4. Mass air flow and intake air temperature sensor
  5. Accelerator pedal position sensor
  1. Poor acceleration
  1. Manifold absolute pressure sensor
  2. Mass air flow and intake air temperature sensor
  3. Electronic throttle control
  4. Fuel injection parts (4)
  5. Fuel pump and fuel pump relay
  6. Engine coolant temperature sensor (*2)
  7. Crankshaft position sensor (3)
  8. Camshaft position sensor (3)
  9. A/C switch and A/C relay
  10. Engine torque control signal circuit
  11. Ignition parts (1)
  12. Accelerator pedal position sensor
  1. Engine stalls, hesitates, or sputters at acceleration.
  1. Manifold absolute pressure sensor
  2. Mass air flow and intake air temperature sensor
  3. Engine coolant temperature sensor (*2)
  4. Crankshaft position sensor (3)
  5. Camshaft position sensor (3)
  6. Purge control solenoid valve
  7. Fuel injection parts (4)
  8. Fuel pump and fuel pump relay
  9. Electronic throttle control
  1. Surging
  1. Manifold absolute pressure sensor
  2. Mass air flow and intake air temperature sensor
  3. Engine coolant temperature sensor (*2)
  4. Crankshaft position sensor (3)
  5. Camshaft position sensor (3)
  6. Fuel injection parts (4)
  7. Electronic throttle control
  8. Fuel pump and fuel pump relay
  1. Spark knock
  1. Manifold absolute pressure sensor
  2. Mass air flow and intake air temperature sensor
  3. Engine coolant temperature sensor
  4. Knock sensor
  5. Fuel injection parts (4)
  6. Fuel pump and fuel pump relay
  1. After burning in exhaust system
  1. Manifold absolute pressure sensor
  2. Mass air flow and intake air temperature sensor
  3. Engine coolant temperature sensor (*2)
  4. Fuel injection parts (4)
  5. Fuel pump and fuel pump relay
(1) Check ignition coil and spark plug.
(2) Indicate the symptom occurring only in cold temperatures.
(3) Ensure secure installation.
(4) Check fuel injector, fuel pressure regulator and fuel filter.
(5) Inspect for air leak in air intake system.
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