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General Diagnostic Table: Inspection: Engine

NOTE: Malfunction of parts other than those listed is also possible. < Ref. to ENGINE TROUBLE IN GENERAL . >
GENERAL DIAGNOSTIC CHART

Symptom Problem parts
1. Engine stalls during idling.
  1. Idle air control solenoid valve
  2. Intake manifold pressure sensor
  3. Intake air temperature sensor
  4. Intake air temperature and pressure sensor
  5. Ignition parts ((1))
  6. Engine coolant temperature sensor ((2))
  7. Crankshaft position sensor ((3))
  8. Camshaft position sensor ((3))
  9. Fuel injection parts ((4))
2. Rough idling
  1. Idle air control solenoid valve
  2. Intake manifold pressure sensor
  3. Intake air temperature sensor
  4. Intake air temperature and pressure sensor
  5. Engine coolant temperature sensor ((2))
  6. Ignition parts ((1))
  7. Air intake system ((5))
  8. Fuel injection parts ((4))
  9. Throttle position sensor
  10. Crankshaft position sensor ((3))
  11. Camshaft position sensor ((3))
  12. Oxygen sensor
  13. Fuel pump and fuel pump relay
3. Engine does not return to idle.
  1. Idle air control solenoid valve
  2. Engine coolant temperature sensor
  3. Accelerator cable ((6))
  4. Throttle position sensor
  5. Intake manifold pressure sensor
  6. Intake air temperature sensor
  7. Intake air temperature and pressure sensor
4. Poor acceleration
  1. Intake manifold pressure sensor
  2. Intake air temperature sensor
  3. Intake air temperature and pressure sensor
  4. Throttle position sensor
  5. Fuel injection parts ((4))
  6. Fuel pump and fuel pump relay
  7. Engine coolant temperature sensor ((2))
  8. Crankshaft position sensor ((3))
  9. Camshaft position sensor ((3))
  10. A/C switch and A/C cut relay
  11. Engine torque control signal circuit
  12. Ignition parts ((1))
5. Engine stalls or engine speed drops or hesitates at acceleration.
  1. Intake manifold pressure sensor
  2. Intake air temperature sensor
  3. Intake air temperature and pressure sensor
  4. Engine coolant temperature sensor ((2))
  5. Crankshaft position sensor ((3))
  6. Camshaft position sensor ((3))
  7. Purge control solenoid valve
  8. Fuel injection parts ((4))
  9. Throttle position sensor
  10. Fuel pump and fuel pump relay
6. Surge
  1. Intake manifold pressure sensor
  2. Intake air temperature sensor
  3. Intake air temperature and pressure sensor
  4. Engine coolant temperature sensor ((2))
  5. Crankshaft position sensor ((3))
  6. Camshaft position sensor ((3))
  7. Fuel injection parts ((4))
  8. Throttle position sensor
  9. Fuel pump and fuel pump relay
7. Spark knock
  1. Intake manifold pressure sensor
  2. Intake air temperature sensor
  3. Intake air temperature and pressure sensor
  4. Engine coolant temperature sensor
  5. Knock sensor
  6. Fuel injection parts ((4))
  7. Fuel pump and fuel pump relay
8. After burning in exhaust system
  1. Intake manifold pressure sensor
  2. Intake air temperature sensor
  3. Intake air temperature and pressure sensor
  4. Engine coolant temperature sensor ((2))
  5. Fuel injection parts ((4))
  6. Fuel pump and fuel pump relay
(1) Check ignition coil & ignitor assembly 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.
(6) Adjust accelerator cable.
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