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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 . >
DIAGNOSTIC PROCEDURE CHART

Symptom Problem 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))
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
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
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. A/C switch and A/C cut relay
  10. Engine torque control signal circuit
  11. Ignition parts ((1))
  12. EGR 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. 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 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.
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