This procedure covers removal and replacement of the intake manifold on a 2015 Kia Forte with 1.8L I4 engine, including disconnection of all necessary components and proper torque sequence during reinstallation.

Warnings

Tools required

Parts

• Intake manifold gasket × 1 — Use OEM specification
• Throttle body gasket × 1 — Use OEM specification
• PCV valve grommet (if damaged) × 1 — Use OEM specification

Fluids

• Hyundai/Kia Long Life Coolant (Green) — 1 qt

Preparation

1. Ensure engine is completely cool to the touch
2. Disconnect negative battery cable and wait 3 minutes
3. Relieve fuel system pressure by removing fuel pump fuse and cranking engine until it stalls
4. Remove engine cover by pulling upward on mounting points
5. Drain coolant to level below throttle body by opening radiator drain plug into appropriate container
6. Place shop rags around work area to catch any residual coolant or fuel

Procedure

1. 1

   Disconnect air intake system
   Loosen clamp on air intake tube at throttle body. Disconnect mass airflow sensor electrical connector. Remove air intake tube and air filter housing assembly from engine bay. Disconnect breather hoses from valve cover.
2. 2

   Disconnect throttle body connections
   Disconnect throttle position sensor electrical connector from throttle body. Disconnect coolant hoses from throttle body (two hoses - inlet and outlet). Use pliers to slide hose clamps back and carefully twist hoses to break seal before pulling off.
   ⚠Residual coolant will drain from hoses. Have shop rags ready to catch spillage.
3. 3

   Remove throttle body
   Remove four throttle body mounting bolts using 10mm socket. Carefully pull throttle body away from intake manifold. Remove and discard throttle body gasket. Cover throttle body opening with clean shop rag to prevent debris entry.
   Torque spec

   Throttle Body Bolts10 Nm (7 lb-ft)
4. 4

   Disconnect fuel system components
   Disconnect fuel injector electrical connectors (four connectors). Disconnect fuel supply line from fuel rail using appropriate fuel line disconnect tool. Place shop rag under connection to catch residual fuel. Disconnect fuel pressure regulator vacuum hose.
   ⚠Even with pressure relieved, fuel will spill from lines. Ensure adequate ventilation and have fire extinguisher nearby.
5. 5

   Remove fuel rail assembly
   Remove fuel rail mounting bolts using 10mm socket. Carefully pull fuel rail upward to disengage injectors from intake manifold. Fuel injectors will come out with rail. Set fuel rail assembly aside in safe location away from work area.
   Torque spec

   Fuel Rail Bolts12 Nm (9 lb-ft)
6. 6

   Disconnect vacuum lines and sensors
   Disconnect brake booster vacuum hose from intake manifold. Disconnect PCV hose from valve cover and intake manifold. Disconnect EVAP purge valve hose from manifold. Disconnect any remaining vacuum lines, taking photos or labeling for reassembly reference. Disconnect manifold absolute pressure (MAP) sensor electrical connector if equipped.
7. 7

   Remove intake manifold support bracket
   Locate support bracket connecting intake manifold to engine block on driver side. Remove mounting bolts securing bracket using 12mm or 13mm socket. Remove bracket and set aside.
   Torque spec

   Mounting Bolts45 Nm (33 lb-ft)
8. 8

   Remove intake manifold
   Remove intake manifold mounting bolts and nuts in reverse order of tightening sequence (working from outer bolts toward center). There are typically 6 mounting fasteners. Carefully lift intake manifold away from cylinder head. Remove and discard intake manifold gasket. Immediately cover cylinder head intake ports with clean shop rags to prevent debris entry.
   ⚠Manifold may be stuck due to gasket seal. Gently work it loose - do not pry against machined sealing surfaces as this will cause damage and leaks.
   Torque spec

   Intake Manifold Bolts25 Nm (18 lb-ft)
9. 9

   Clean mating surfaces
   Remove all gasket material from intake manifold and cylinder head mating surfaces using plastic scraper. Do not use metal scrapers that could gouge aluminum surfaces. Clean surfaces thoroughly with brake cleaner and lint-free shop rags. Inspect manifold for cracks or warpage. Clean throttle body mounting surface on intake manifold.
   ⚠Ensure no gasket material or debris falls into intake ports. Keep ports covered except when actively cleaning the mating surface directly around them.
10. 10

    Install new intake manifold gasket and manifold
    Remove shop rags from intake ports. Position new intake manifold gasket on cylinder head, aligning all port openings. Carefully lower intake manifold into position, ensuring gasket stays aligned. Start all intake manifold bolts by hand to ensure proper thread engagement. Tighten bolts in sequence from center outward to specified torque in two steps: first to 12 Nm, then final pass to 25 Nm (18 lb-ft). Verify tightening sequence in service manual before proceeding.
    ℹ️Proper torque sequence is critical to prevent vacuum leaks and gasket failure. Sequence typically starts at center and works outward in alternating pattern.
    Torque spec

    Intake Manifold Bolts25 Nm (18 lb-ft)
11. 11

    Reinstall support bracket
    Position intake manifold support bracket between manifold and engine block. Install mounting bolts and torque to specification.
    Torque spec

    Mounting Bolts45 Nm (33 lb-ft)
12. 12

    Reinstall fuel rail assembly
    Lubricate fuel injector O-rings with small amount of clean engine oil. Carefully align fuel injectors with intake manifold bores and press fuel rail assembly straight down until injectors are fully seated. Install fuel rail mounting bolts and torque in proper sequence to specification per service manual.
    Torque spec

    Fuel Rail Bolts12 Nm (9 lb-ft)
13. 13

    Reconnect fuel system and vacuum lines
    Reconnect fuel supply line to fuel rail until it clicks into place. Tug gently to verify secure connection. Reconnect all fuel injector electrical connectors. Reconnect brake booster vacuum hose, PCV hose, EVAP purge valve hose, and all other vacuum lines removed during disassembly. Reconnect MAP sensor connector if equipped. If PCV valve was removed, reinstall with new grommet if needed and torque to specification.
    Torque spec

    PCV Valve8 Nm (6 lb-ft)
14. 14

    Reinstall throttle body
    Install new throttle body gasket on intake manifold. Position throttle body on manifold and install mounting bolts. Torque bolts to specification per service manual sequence. Reconnect coolant hoses to throttle body and secure with hose clamps. Reconnect throttle position sensor electrical connector.
    Torque spec

    Throttle Body Bolts10 Nm (7 lb-ft)
15. 15

    Reinstall air intake system
    Reinstall air filter housing and air intake tube. Reconnect mass airflow sensor electrical connector. Tighten air intake tube clamp at throttle body. Reconnect breather hoses to valve cover. Reinstall engine cover.

Reassembly

1. Refill cooling system with Hyundai/Kia Long Life Coolant to proper level
2. Reconnect negative battery cable
3. Reinstall fuel pump fuse
4. Turn ignition to ON position (do not start) for 5 seconds, then OFF. Repeat 3 times to prime fuel system and check for fuel leaks
5. Start engine and allow to reach operating temperature while monitoring for coolant, fuel, or vacuum leaks
6. Bleed cooling system by running engine with radiator cap off until thermostat opens, adding coolant as needed

Verification

• Inspect all connections for fuel, coolant, or vacuum leaks with engine running
• Verify smooth idle with no vacuum leak symptoms (rough idle, high idle, or lean codes)
• Check throttle response is normal with no hesitation
• Verify no check engine light or diagnostic trouble codes present
• Recheck coolant level after cooling system has been bled and topped off
• Test drive vehicle to confirm normal operation under load

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