Engine Intake System - Intake (induction) (sti) Subaru Impreza WRX STI GR

Scheme 35

Tightening torque: N.m (kgf-m, ft-lb)

T1: 1 (0.1, 0.7)

T2: 2.5 (0.3, 1.8)

T3: 6 (0.6, 4.4)

T4: 7.5 (0.8, 5.5)

Scheme 36

Tightening torque: N.m (kgf-m, ft-lb)

T1: 3 (0.3, 2.2)

T2: 19 (1.9, 14.0)

Scheme 37

Tightening torque: N.m (kgf-m, ft-lb)

T1: 3 (0.3, 2.2)

T2: 5.5 (0.6, 4.1)

T3: 16 (1.6, 11.8)

Scheme 38

Tightening torque: N.m (kgf-m, ft-lb)

T1: 4.9 (0.5, 3.6)

T2: 16 (1.6, 11.8)

T3: 20 (2.0, 14.8)

T4: 23 (2.3, 17.0)

T5: 33 (3.4, 24.3)

CAUTION

1. Wear appropriate work clothing, including a cap, protective goggles and protective shoes when performing any work.
2. Remove contamination including dirt and corrosion before removal, installation or disassembly.
3. Keep the disassembled parts in order and protect them from dust and dirt.
4. Before removal, installation or disassembly, be sure to clarify the failure. Avoid unnecessary removal, installation, disassembly and replacement.
5. Vehicle components are extremely hot after driving. Be wary of receiving burns from heated parts.
6. Be sure to tighten fasteners including bolts and nuts to the specified torque.
7. Place shop jacks or rigid racks at the specified points.
8. Before disconnecting connectors of sensors or units, be sure to disconnect the ground cable from the battery.

GENERAL TOOL

GENERAL TOOL SPECIFICATION

Scheme 39

Scheme 40

Scheme 41

1. Disconnect the ground cable from battery.
2. Remove the air intake duct. REMOVAL, Air Intake Duct.
3. Disconnect the connector (A) from air flow and intake air temperature sensor.
4. Remove the clips (B) from the air cleaner case (front).
5. Open the air cleaner case, and remove the air cleaner element.

INSTALLATION

Install in the reverse order of removal.

Note. Check that there are no foreign objects in the air cleaner case.

INSPECTION

Replace if excessively damaged or dirty.

Scheme 42

Scheme 43

1. Disconnect the ground cable from battery.
2. Remove the air intake duct. REMOVAL, Air Intake Duct.
3. Disconnect the connector (A) from air flow and intake air temperature sensor.
4. Loosen the clamp (B) which holds the air intake boot.
5. Remove the clip (C) from the air cleaner case (front).
6. Remove the air cleaner case (rear) and air intake boot.
7. Remove the air cleaner element.
8. Remove the bolt (A) and nut (B) which secure the air cleaner case (front) to the body.
9. Remove the air cleaner case (front).

Scheme 44

Scheme 45

1. Install the bolt (A) and nut (B) which secure the air cleaner case (front) to the body. Tightening torque: Bolt (A) 6 N.m (0.6 kgf-m, 4.4 ft-lb) Nut (B) 7.5 N.m (0.8 kgf-m, 5.5 ft-lb)
2. Install the air cleaner element.
3. Install the air cleaner case (rear) and air intake boot. NOTE: When installing the air cleaner case (rear), align the protrusion of the air cleaner case (rear) to the hole on the air cleaner case (front) to install. Tightening torque: 2.5 N.m (0.3 kgf-m, 1.8 ft-lb)
4. Install the clip (B) to the air cleaner case (front).
5. Connect the connector (A) to the mass air flow and intake air temperature sensor.
6. Install the air intake duct. INSTALLATION, Air Intake Duct.
7. Connect the ground cable to battery.

Check for cracks or loose connections.

REMOVAL

Remove the clip which secures the air intake duct, and remove the air intake duct.

Scheme 46

Install in the reverse order of removal.

1. Check for cracks or loose connections.
2. Inspect that no foreign objects in the air intake duct.

Scheme 47

1. Disconnect the ground cable from battery.
2. Remove the intake manifold. Ref. to «REMOVAL»(/subaru/impreza-wrx-sti/gr-2007-2011/remont/fuel-system/#fuel-injection-system-sti) , Intake Manifold.
3. Remove the sensor, engine harness and fuel pipe attached to the intake manifold. Ref. to «DISASSEMBLY»(/subaru/impreza-wrx-sti/gr-2007-2011/remont/fuel-system/#fuel-injection-system-sti) , Intake Manifold.
4. Remove the intake duct from intake manifold.

Install in the reverse order of removal.

Tightening torque: 19 N.m (1.9 kgf-m, 14.0 ft-lb)

Scheme 48

Scheme 49

Scheme 50

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Scheme 52

Scheme 53

1. Disconnect the PCV hose from the PCV pipe.
2. Remove the clip (A) which holds the air by-pass hose on the air by-pass valve and disconnect vacuum hose (B) from the air by-pass valve.
3. Loosen the clamp (C) holding the intake duct to the turbocharger.
4. Loosen the clamp (D) holding the air duct hose to the intercooler.
5. Remove the bolts which secure the intercooler to the intercooler stay, and remove the intercooler.
6. Remove the intercooler stay.

Install in the reverse order of removal.

Tightening torque: 16 N.m (1.6 kgf-m, 11.8 ft-lb)

Tightening torque: 3 N.m (0.3 kgf-m, 2.2 ft-lb)

Scheme 54

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Scheme 56

Scheme 57

1. Remove the intercooler duct from the intercooler.
2. Remove the air by-pass valve and PCV pipe from the intercooler.
3. Remove the intake duct from intercooler duct.

Scheme 58

1. Install the intake duct to the intercooler duct. Tightening torque: 3 N.m (0.3 kgf-m, 2.2 ft-lb)
2. Install the air by-pass valve and the PCV pipe to the intercooler. NOTE: Use a new gasket. Tightening torque: T1: 5.5 N.m (0.6 kgf-m, 4.1 ft-lb) T2: 16 N.m (1.6 kgf-m, 11.8 ft-lb)
3. Install the intercooler duct to the intercooler. NOTE: Use a new gasket. Tightening torque: 16 N.m (1.6 kgf-m, 11.8 ft-lb)

Check for cracks or loose connections.

Scheme 59

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Scheme 65

Scheme 66

1. Set the vehicle on a lift.
2. Disconnect the ground cable from battery.
3. Lift up the vehicle.
4. Drain approximately 3.0 l (3.2 US qt, 2.6 lmp qt) of coolant. Ref. to «DRAINING OF ENGINE COOLANT»(/subaru/impreza-wrx-sti/gr-2007-2011/remont/cooling-system-mechanical/#engine-cooling-system-sti) , REPLACEMENT, Engine Coolant.
5. Lower the vehicle.
6. Remove the intercooler. REMOVAL, Intercooler.
7. Remove the intercooler stay.
8. Remove the center exhaust pipe. Ref. to «REMOVAL»(/subaru/impreza-wrx-sti/gr-2007-2011/remont/exhaust/#exhaust-system-sti) , Center Exhaust Pipe.
9. Lower the vehicle.
10. Remove the joint pipe from the turbocharger.
11. Disconnect the engine coolant hose from the upper side of the water pipe.
12. Disconnect the air control hose (A), and loosen the clamp holding the intake duct to the turbocharger.
13. Remove the oil inlet pipe from the turbocharger.
14. Disconnect the engine coolant hose from the lower side of the water pipe.
15. Disconnect the oil outlet hose from the oil outlet pipe, and remove the turbocharger.
16. Remove the turbocharger stay.

Scheme 67

Scheme 68

1. Install the turbocharger stay. Tightening torque: T1: 33 N.m (3.4 kgf-m, 24.3 ft-lb) T2: 42.5 N.m (4.3 kgf-m, 31.3 ft-lb)
2. Connect the oil outlet hose to the oil outlet pipe.
3. Connect the engine coolant hose to the lower side of the water pipe.
4. Install the oil inlet pipe to turbocharger. NOTE: Use a new gasket. When tightening, never rotate the part indicated as (A) in the figure. Tightening torque: T1: 16 N.m (1.6 kgf-m, 11.8 ft-lb) T2: 20 N.m (2.0 kgf-m, 14.8 ft-lb)
5. Connect the air control hose (A), and install the intake duct to the turbocharger. Tightening torque: 3 N.m (0.3 kgf-m, 2.2 ft-lb)
6. Connect the engine coolant hoses to the upper side of the water pipe.
7. Install the joint pipe to turbocharger. NOTE: Use a new gasket. Tightening torque: 42.5 N.m (4.3 kgf-m, 31.3 ft-lb)
8. Lift up the vehicle.
9. Install the center exhaust pipe. Ref. to «INSTALLATION»(/subaru/impreza-wrx-sti/gr-2007-2011/remont/exhaust/#exhaust-system-sti) , Center Exhaust Pipe.
10. Lower the vehicle.
11. Install the intercooler stay. Tightening torque: 16 N.m (1.6 kgf-m, 11.8 ft-lb)
12. Install the intercooler. INSTALLATION, Intercooler.
13. Connect the ground cable to battery.
14. Fill engine coolant. Ref. to «FILLING OF ENGINE COOLANT»(/subaru/impreza-wrx-sti/gr-2007-2011/remont/cooling-system-mechanical/#engine-cooling-system-sti) , REPLACEMENT, Engine Coolant.

Scheme 69

Scheme 70

1. Remove the intercooler. REMOVAL, Intercooler.
2. Remove the turbocharger upper cover.
3. Remove the boost hose (B) from the waste gate actuator (A) of the turbocharger, and connect the Mighty Vac to the waste gate actuator (A).
4. Pressurize slowly with the Mighty Vac, and measure the pressure when the control rod stroke (D) becomes 2 mm (0.08 in). If it is not within the standard, replace the turbocharger assembly. CAUTION: Do not pressurize over 89.9 kPa (0.92 kgf/cm 2 , 13.0 psi) to prevent damaging the waste gate actuator. Operating pressure (Control rod stroke 2 mm (0.08 in)): Standard 74.7 - 80.8 kPa (0.76 - 0.82 kgf/cm 2 , 10.8 - 11.7 psi)
5. After inspection, install the related parts in the reverse order of removal. Tightening torque: 7.5 N.m (0.8 kgf-m, 5.5 ft-lb)

OIL PIPE AND WATER PIPE

1. Check that there are no oil leakage or water leakage from the pipe attachment section.
2. Check for cracks or loose connections.

Scheme 71

1. Remove the air by-pass valve (A) from the inter-cooler.
2. Disconnect the air by-pass hose (B) and vacuum hose (C) from the air by-pass valve (A).

Install in the reverse order of removal.

Note. Use a new gasket.

Tightening torque: 16 N.m (1.6 kgf-m, 11.8 ft-lb)

Scheme 72

The resonator chamber and air cleaner case are integrated into one unit; therefore, refer to Air Cleaner Case for the removal procedure. REMOVAL, Air Cleaner Case.

The resonator chamber and air cleaner case are integrated into one unit; therefore, refer to Air Cleaner Case for installation procedure. INSTALLATION, Air Cleaner Case.

Check for cracks or loose connections.

See also:
• REMOVAL
• DRAINING OF ENGINE COOLANT
• REMOVAL