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General Diagnostic Table: Inspection: Engine

NOTE: Malfunction of parts other than those listed is also possible. Refer to ENGINE TROUBLE IN GENERAL ME(H4SO)-95, Engine Trouble in General.
Symptoms Faulty parts
1. Engine stalls during idling.
  1. Manifold absolute pressure sensor
  2. Mass air flow and intake air temperature sensor
  3. Ignition parts ((1))
  4. Engine coolant temperature sensor ((2))
  5. Crankshaft position sensor ((3))
  6. Camshaft position sensor ((3))
  7. Fuel injection parts ((4))
  8. Electronic throttle control
2. Rough idling
  1. Manifold absolute pressure sensor
  2. Mass air flow and intake air temperature sensor
  3. Engine coolant temperature sensor ((2))
  4. Ignition parts ((1))
  5. Air intake system ((5))
  6. Fuel injection parts ((4))
  7. Electronic throttle control
  8. Crankshaft position sensor ((3))
  9. Camshaft position sensor ((3))
  10. Oxygen sensor
  11. Fuel pump and fuel pump relay
  12. EGR valve
  13. Oil switching solenoid valve
3. Engine does not return to idle.
  1. Engine coolant temperature sensor
  2. Electronic throttle control
  3. Manifold absolute pressure sensor
  4. Mass air flow and intake air temperature sensor
  5. EGR valve
  6. Accelerator pedal position sensor
  7. Oil temperature sensor
4. 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. Engine torque control signal circuit
  10. Ignition parts ((1))
  11. EGR valve
  12. Accelerator pedal position sensor
  13. Oil temperature sensor
  14. Oil switching solenoid valve
5. 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. Electronic throttle control
  9. Fuel pump and fuel pump relay
  10. EGR valve
6. Surging
  1. Mass air flow and intake air temperature sensor
  2. Manifold absolute pressure 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
  9. EGR valve
7. Spark knock
  1. Mass air flow and intake air temperature sensor
  2. Manifold absolute pressure sensor
  3. Engine coolant temperature sensor
  4. Knock sensor
  5. Fuel injection parts ((4))
  6. Fuel pump and fuel pump relay
  7. EGR valve
  8. Oil switching solenoid valve
8. After burning in exhaust system
  1. Mass air flow and intake air temperature sensor
  2. Manifold absolute pressure 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 the secure installation.
(4) Check fuel injector, fuel pressure regulator and fuel filter.
(5) Inspect air leak in air intake system.
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