Subaru Legacy IV (2008 year). Manual - part 174

EN(H4SO)(diag)-299

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DM:DTC P2229 BAROMETRIC PRESSURE CIRCUIT HIGH

DTC DETECTING CONDITION:
• Immediately at fault recognition
• GENERAL DESCRIPTION <Ref. to GD(H4SO)-200, DTC P2229 BAROMETRIC PRESSURE CIRCUIT
HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4SO)(diag)-50,
OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4SO)(diag)-41, PROCEDURE,
Inspection Mode.>.

Step

Check

Yes

No

1

CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed?

Check DTC using 
“List of Diagnostic 
Trouble Code 
(DTC)”. <Ref. to 
EN(H4SO)(diag)-
80, List of Diagnos-
tic Trouble Code 
(DTC).>

Replace the ECM. 
<Ref. to 
FU(H4SO)-39,
Engine Control 
Module (ECM).>

NOTE:
The barometric
pressure sensor is
built into the ECM.

EN(H4SO)(diag)-300

General Diagnostic Table

ENGINE (DIAGNOSTICS)

21.General Diagnostic Table

A: INSPECTION

1. ENGINE

NOTE:
Malfunction of parts other than those listed is also possible. <Ref. to ME(H4SO)-96, Engine Trouble in Gen-
eral.>

Symptoms

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, engine sags or hesitates 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

EN(H4SO)(diag)-301

General Diagnostic Table

ENGINE (DIAGNOSTICS)

*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.

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-burn 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

Symptoms

Problem parts

EN(H4SO)(diag)-302

General Diagnostic Table

ENGINE (DIAGNOSTICS)