Air Intake System (h4dotc) Subaru Impreza WRX GD/GG рестайлинг

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CAUTION

1. Wear working clothing, including a cap, protective goggles, and protective shoes during operation.
2. Remove contamination including dirt and corrosion before removal, installation or disassembly.
3. Keep the disassembled parts in order and protect them from dust or dirt.
4. Before removal, installation or disassembly, be sure to clarify the failure. Avoid unnecessary removal, installation, disassembly, and replacement.
5. Be careful not to burn your hands, because each part on the vehicle is hot after running.
6. Be sure to tighten fasteners including bolts and nuts to the specified torque.
7. Place shop jacks or safety stands at the specified points.
8. Before disconnecting electrical connectors of sensor or units, be sure to disconnect negative terminal from battery.

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1. Disconnect the ground terminal from battery.
2. Disconnect the connector from mass air flow sensor.
3. Loosen the clamp (A) which connects air intake boot to intake duct.
4. Remove the two clips (B) from air cleaner upper cover.
5. Remove the air cleaner upper cover.
6. Remove the air cleaner element.
7. Remove the air cleaner lower case.

INSTALLATION

Install in the reverse order of removal.

1. Tightening torque: 33 N.m (3.4 kgf-m, 25 ft-lb)

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1. Tightening torque: 2.5 N.m (0.25 kgf-m, 1.8 ft-lb)

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INSPECTION

Replace if excessively damaged or dirty.

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1. Remove the bolts which install air intake duct on the front side of body.

Install in the reverse order of removal.

1. Tightening torque: 7.5 N.m (0.76 kgf-m, 5.5 ft-lb)

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1. Inspect for cracks and loose connections.
2. Inspect that no foreign objects are mixed in the air intake duct.

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1. Disconnect the ground terminal from battery.
2. Remove the intake manifold, see «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#air-intake-system-h4dotc) , Intake Manifold.
3. Remove the sensor, engine harness, and fuel pipe attached to the intake manifold, see «DISASSEMBLY»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#air-intake-system-h4dotc) , Intake Manifold
4. Remove the intake duct from intake manifold.

Install in the reverse order of removal.

1. Tightening torque: 19 N.m (1.9 kgf-m, 13.7 ft-lb)

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1. Disconnect the air by-pass hoses from intercooler.
2. Separate the air by-pass valve from intercooler.
3. Remove the bolts which secure intercooler to bracket.
4. Separate the intercooler air duct from turbocharger.
5. Separate the intercooler from throttle body.

Install in the reverse order of removal.

1. Tightening torque: 16 N.m (1.6 kgf-m, 11.7 ft-lb)

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DISASSEMBLY

Remove the intercooler ducts from intercooler.

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ASSEMBLY

Assemble in the reverse order of disassembly.

1. Tightening torque: 16 N.m (1.6 kgf-m, 11.7 ft-lb)

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1. Set the vehicle on the lift.
2. Disconnect the ground terminal from battery.
3. Remove the center exhaust pipe. See «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/exhaust/#exhaust-system-h4dotc) , Center Exhaust Pipe.
4. Lower the vehicle.
5. Separate the turbocharger joint pipe from turbocharger.
6. Disconnect the engine coolant hose which is connected to coolant filler tank.
7. Loosen the clamp which secures turbocharger to air inlet duct.
8. Remove the bolt which secures bracket of oil pipe to turbocharger.
9. Remove the oil pipe from turbocharger.
10. Remove the turbocharger bracket.
11. Disconnect the oil outlet hose from pipe.
12. Take out the turbocharger from engine compartment.

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1. Connect the oil outlet hose to outlet pipe.
2. Install the turbocharger to air intake duct.
3. Install the oil pipe to turbocharger.
4. Install the joint pipe to turbocharger. NOTE: Replace the gasket with a new one. Tightening torque: 30 N.m (3.1 kgf-m, 22.4 ft-lb)
5. Install the turbocharger bracket.
6. Connect the engine coolant hose which is connected to coolant filler tank.
7. Lift-up the vehicle.
8. Install the center exhaust pipe. See «INSTALLATION»(/subaru/impreza-wrx/gdgg-2002-2005/remont/exhaust/#exhaust-system-h4dotc) , Center Exhaust Pipe.

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1. Remove the air by-pass valve from intercooler.
2. Disconnect the air by-pass hoses from air by-pass valve.

Install in the reverse order of removal.

1. Tightening torque: 16 N.m (1.6 kgf-m, 11.7 ft-lb)

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1. Set the vehicle on a lift.
2. Remove the air intake duct, see «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#air-intake-system-h4dotc) , Air Intake Duct.
3. Remove the air cleaner lower case, see «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#air-intake-system-h4dotc) , Air Cleaner.
4. Remove the resonator chamber mounting bolt on the right of engine compartment.
5. Remove the front right tire, and lift the vehicle.
6. Remove the front mudguard RH.
7. Remove the resonator chamber from the inside front fender.

Install in the reverse order of removal.

1. Tightening torque: 7.5 N.m (0.76 kgf-m, 5.5 ft-lb)

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Inspect for cracks and loose connections. Check that no foreign objects are mixed in the resonator chamber.

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1. Release the fuel pressure. See «RELEASING OF FUEL PRESSURE»(/subaru/impreza-wrx/gdgg-2002-2005/remont/fuel-system/#fuel-system-dohctc__releasing-of-fuel-pressure) , OPERATION, Fuel.
2. Open the fuel filler lid and remove the fuel filler cap.
3. Disconnect the battery ground cable.
4. Lift up the vehicle.
5. Remove the under cover.
6. Drain the coolant about 3.0 l (3.2 US qt, 2.6 Imp qt).
7. Remove the air cleaner upper cover and air intake boot, see «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#air-intake-system-h4dotc) , Air Cleaner.
8. Remove the air cleaner element.
9. Remove the intercooler, see «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#air-intake-system-h4dotc) , Intercooler.
10. Disconnect the accelerator cable.
11. Remove the coolant filler tank. See «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/cooling-fan/#engine-cooling-system) , Coolant Filler Tank
12. Remove the power steering pump. Remove the front side V-belt. «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#engine-mechanical-20l-dohctc) , V-belt. Disconnect the power steering switch connector. Remove the bolts which secure the power steering pipe brackets to the intake manifold. NOTE: Do not disconnect the power steering hose. Remove the bolts which secure the power steering pump bracket. Remove the power steering tank from the bracket by pulling it upward. Place power steering pump on the right side wheel apron.
13. Disconnect the emission hose from the PCV valve.
14. Disconnect the engine coolant hoses from the throttle body.
15. Disconnect the brake booster hose.
16. Disconnect the pressure hose from the intake duct.
17. Disconnect the engine harness connectors from the bulkhead harness connectors.
18. Disconnect the connectors from the engine coolant temperature sensor (A), oil pressure switch (B) and crankshaft position sensor (C).
19. Disconnect the knock sensor connector.
20. Disconnect the connector from the camshaft position sensor.
21. Disconnect the connector from the ignition coil.
22. Disconnect the engine harness fixed by clip (A) from the bracket.
23. Disconnect the fuel delivery hose, return hose and evaporation hose. CAUTION: Do not spill fuel. Catch fuel from hoses in a container or cloth.
24. Remove the bolts which secure the intake manifold to the cylinder heads.
25. Remove the intake manifold.

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1. Install the intake manifold onto cylinder heads. NOTE: Always use new gaskets. Tightening torque: 25 N.m (2.5 kgf-m, 18.1 ft-lb)
2. Connect the fuel delivery hose, return hose, and evaporation hose.
3. Connect the connector to the oil pressure switch (B), crankshaft position sensor (C) and engine coolant temperature sensor (A).
4. Connect the connector to the knock sensor.
5. Connect the connector to the camshaft position sensor.
6. Connect the connector to the ignition coil.
7. Connect the engine harness with clip (A) to the bracket.
8. Connect the engine harness connector to the bulkhead harness connectors.
9. Connect the brake booster vacuum hose.
10. Connect the engine coolant hoses to the throttle body.
11. Connect the emission hose to the PCV valve.
12. Connect the pressure hose to the intake duct.
13. Install the power steering pump. Install the power steering tank on the bracket. Connect the connector to the power steering pump switch. Install the power steering pump, and tighten the bolts. Tightening torque: 22 N.m (2.2 kgf-m, 15.9 ft-lb) Install the power steering pipe brackets on the right side intake manifold. Install the front side V-belt. See «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#engine-mechanical-20l-dohctc) , V-belt.
14. Install the cooler filler tank. See «INSTALLATION»(/subaru/impreza-wrx/gdgg-2002-2005/remont/cooling-fan/#engine-cooling-system) , Coolant Filler Tank.
15. Connect the accelerator cable.
16. Install the intercooler, see «INSTALLATION»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#air-intake-system-h4dotc) , Intercooler.
17. Install the air cleaner element.
18. Install the air cleaner upper cover and air intake duct as a unit, see «INSTALLATION»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#air-intake-system-h4dotc__installation) , Air Cleaner.
19. Connect the connector to the fuel pump relay.
20. Connect the battery ground cable.
21. Lift up the vehicle.
22. Install the under cover.
23. Fill the coolant. See «FILLING OF ENGINE COOLANT»(/subaru/impreza-wrx/gdgg-2002-2005/remont/cooling-fan/#engine-cooling-system) , Engine Coolant.

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1. Remove the fuel pipe protector LH.
2. Remove the fuel pipe protector RH.
3. Remove the engine ground terminal from the intake manifold.
4. Disconnect the connector from the throttle position sensor (A), idle air control solenoid valve (B) and pressure sensor (C).
5. Disconnect the engine harness fixed by clip (D) from the intake manifold.
6. Remove the throttle body from the intake manifold.
7. Disconnect the connector from the fuel injector.
8. Disconnect the connector from the tumble generator valve actuator.
9. Disconnect the connector from the tumble generator valve sensor.
10. Disconnect the connector from the purge control solenoid valve.
11. Remove the purge control solenoid valve.
12. Disconnect the evaporation hose from the intake manifold.
13. Disconnect the evaporation hoses from the purge valve.
14. Remove the two bolts which hold the fuel pipes on the left side of intake manifold.
15. Remove the bolt which hold the fuel injector pipe onto intake manifold. LH SIDE RH SIDE
16. Remove the fuel injector.
17. Remove the harness bracket which hold the engine harness onto intake manifold.
18. Remove the engine harness from the intake manifold.
19. Loosen the clamp which holds the front left side fuel hose to injector pipe and remove the pipe from clamp.
20. Remove the fuel injector pipe LH.
21. Remove the bolts which installs the fuel pipe on intake manifold.
22. Remove the fuel pipe assembly and pressure regulator, from the intake manifold.
23. Remove the intake duct from the intake manifold.
24. Remove the tumble generator valve assembly from the intake manifold.

Note. Replace the gasket with a new one.

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1. Install the tumble generator valve assembly to the intake manifold. Tightening torque: 8.25 N.m (0.84 kgf-m, 6.1 ft-lb)
2. Install the air intake duct to the intake manifold. Tightening torque: 19 N.m (1.94 kgf-m, 13.7 ft-lb)
3. Install the fuel pipe assembly and pressure regulator, to the intake manifold. Tightening torque: 4.9 N.m (0.5 kgf-m, 3.6 ft-lb)
4. Install the fuel injector pipe LH.
5. Connect the left side fuel hose to injector pipe, and tighten the clamp screw.
6. Install the engine harness to the intake manifold.
7. Install the harness bracket which hold the engine harness onto intake manifold. Tightening torque: 19 N.m (1.94 kgf-m, 13.7 ft-lb)
8. Install the fuel injectors.
9. Tighten the bolt which install the fuel injector pipe onto intake manifold. Tightening torque: 19 N.m (1.94 kgf-m, 13.7 ft-lb) LH SIDE RH SIDE
10. Tighten the two bolts which install the fuel pipes on the left side of intake manifold. Tightening torque: 4.9 N.m (0.5 kgf-m, 3.6 ft-lb)
11. Connect the evaporation hoses to the purge valve. CAUTION: Carefully connect the evaporation hoses.
12. Connect the evaporation hose to the intake manifold.
13. Install the purge control solenoid valve. Tightening torque: 16 N.m (1.6 kgf-m, 11.8 ft-lb)
14. Connect the hoses to the purge control solenoid valve. CAUTION: Carefully connect the evaporation hoses.
15. Connect the connector to the purge control solenoid valve.
16. Connect the connector to the tumble generator valve sensor.
17. Connect the connector to the tumble generator valve actuator.
18. Connect the connector to the fuel injector.
19. Install the throttle body to the intake manifold. NOTE: Replace gasket with a new one. Tightening torque: 22 N.m (2.2 kgf-m, 15.9 ft-lb)
20. Connect the connectors to the throttle position sensor (A), idle air control solenoid valve (B) and pressure sensor (C).
21. Connect the engine harness with clip (D) to the intake manifold.
22. Install the engine ground terminal to the intake manifold. Tightening torque: 19 N.m (1.94 kgf-m, 13.7 ft-lb)
23. Install the fuel pipe protector RH. Tightening torque: 19 N.m (1.94 kgf-m, 13.7 ft-lb)
24. Install the fuel pipe protector LH. Tightening torque: 19 N.m (1.94 kgf-m, 13.7 ft-lb)

Make sure the fuel pipe and fuel hoses are not cracked and that connections are tight.

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1. Disconnect the battery ground cable.
2. Remove the intercooler, see «REMOVAL»(/subaru/impreza-wrx/gdgg-2002-2005/remont/mechanical/#air-intake-system-h4dotc) , Intercooler.
3. Disconnect the connector from the throttle position sensor (A), idle air control solenoid valve (B) and pressure sensor (C).
4. Disconnect the accelerator cable.
5. Disconnect the engine coolant hoses from the throttle body.
6. Remove the bolts which secure the throttle body to intake manifold.

Install in the reverse order of removal.

Note. Always use a new gasket.

1. Tightening torque: 22 N.m (2.2 kgf-m, 15.9 ft-lb)

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See also:
• REMOVAL
• RELEASING OF FUEL PRESSURE
• REMOVAL
• REMOVAL
• REMOVAL
• INSTALLATION