Subaru Legacy (2005 year). Manual - part 243
EN(H4SO 2.5)(diag)-257
ENGINE (DIAGNOSTICS)
General Diagnostic Table
19.General Diagnostic Table
A: INSPECTION
1. ENGINE
NOTE:
Malfunction of parts other than those listed is also possible. <Ref. to ME(H4SO 2.0)-89, Engine Trouble in
General.>
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
13) Tumble generator valve
5. Engine stalls, engine sags or hesitates at accel-
eration.
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
11) Tumble generator valve