Exhaust Manifold Gasket

This procedure covers the removal and replacement of exhaust manifold gaskets on the 3.5L EcoBoost V6 engine, including both driver and passenger side manifolds.

Warnings

Tools required

Parts

• Exhaust manifold gasket set (both sides) × 1 — Motorcraft BR3Z-9448-A or equivalent
• Exhaust manifold studs (if damaged) × 1 — Use OEM specification
• Anti-seize compound × 1 — Use nickel-based anti-seize
• O2 sensor (if damaged during removal) × 1 — Use OEM specification

Fluids

• Motorcraft Orange Coolant — 1 qt

Preparation

1. Ensure engine is completely cold to the touch
2. Disconnect negative battery cable and wait 10 minutes for airbag system discharge
3. Raise and safely support vehicle on jack stands
4. Remove engine undershield and splash guards
5. Apply penetrating oil to all exhaust manifold nuts, flange bolts, and oxygen sensor threads
6. Drain approximately 2 quarts of coolant from radiator petcock to lower coolant level below cylinder head

Procedure

1. 1

   Remove intake air system components
   Remove the air filter housing and intake tube assembly to gain access to the passenger side engine bay. Disconnect mass airflow sensor electrical connector. Remove clamps securing intake tube to throttle body and turbocharger inlet. Lift entire assembly out of engine bay.
2. 2

   Disconnect turbocharger coolant lines
   Locate coolant feed and return lines connected to the turbocharger. Place drain pan below connections. Using appropriate wrench, disconnect coolant lines from turbocharger. Cap or plug lines to prevent coolant loss and contamination. Remove coolant line support brackets if present.
3. 3

   Remove heat shields
   Remove the exhaust manifold heat shield by removing all heat shield bolts. Shield may be stuck due to corrosion; carefully pry loose if necessary. Also remove turbocharger heat shield if it interferes with manifold access.
   Torque spec

   Heat Shield Bolts10 Nm (7 lb-ft)
4. 4

   Disconnect oxygen sensors
   Disconnect electrical connectors from both upstream and downstream oxygen sensors. Using oxygen sensor socket, carefully remove oxygen sensors from exhaust manifold and downpipe. If sensors are seized, apply additional penetrating oil and allow to soak. Inspect sensor threads and replace if damaged.
   ⚠Oxygen sensors are fragile. Do not use excessive force or impact tools which may damage the sensor element.
5. 5

   Disconnect EGR tube
   If equipped with EGR, disconnect the EGR tube from the exhaust manifold. Remove the tube fitting using appropriate wrench. EGR tube may require removal of retaining brackets. Set aside carefully to avoid damaging tube or gasket surfaces.
6. 6

   Remove turbocharger downpipe connection
   From underneath vehicle, remove the flange bolts connecting the turbocharger outlet to the downpipe/catalytic converter assembly. Support the downpipe weight with a jack or wire to prevent stress on hangers. Separate the connection and move downpipe aside.
7. 7

   Disconnect turbocharger oil lines
   Disconnect the turbocharger oil feed line from the top of the turbo. Disconnect oil drain tube from bottom of turbocharger to engine block. Have drain pan ready as residual oil will drain out. Cap all openings immediately to prevent contamination.
   ⚠Do not allow dirt or debris to enter turbocharger oil passages. Contamination will cause immediate turbo failure upon startup.
8. 8

   Remove turbocharger mounting bolts
   Remove all turbocharger mounting bolts securing the turbo assembly to the exhaust manifold. Note bolt locations and lengths for reassembly. Carefully lift turbocharger away from manifold and set on clean surface. Do not set turbo on impeller side.
9. 9

   Remove exhaust manifold nuts
   Working from the center outward (hot to cold pattern), remove all exhaust manifold nuts securing the manifold to the cylinder head studs. Use penetrating oil liberally if nuts are difficult to remove. If studs begin to turn with the nut, stop and apply heat carefully or use stud removal techniques.
   ⚠Manifold studs commonly break on removal. If a stud breaks, it must be extracted from the cylinder head using appropriate extraction tools or by drilling and re-tapping.
   Torque spec

   Exhaust Manifold Nuts30 Nm (22 lb-ft)
10. 10

    Remove exhaust manifold
    Once all nuts are removed, carefully work the exhaust manifold away from the cylinder head. Manifold may be stuck to head due to carbon buildup. Gently work it loose, being careful not to damage cylinder head mating surface. Remove manifold from vehicle.
11. 11

    Clean gasket mating surfaces
    Using plastic scraper and wire brush, thoroughly clean all old gasket material from both exhaust manifold and cylinder head mating surfaces. Do not gouge or scratch the sealing surfaces. Use brake cleaner to remove all carbon deposits and oil residue. Inspect cylinder head surface for warping or damage. Inspect manifold for cracks, especially around port openings.
    ⚠Do not use power tools or aggressive abrasives on aluminum cylinder head surface. Damage to sealing surface will cause gasket failure.
12. 12

    Install new exhaust manifold studs if needed
    If any exhaust manifold studs were damaged or removed, install new studs into cylinder head. Apply small amount of anti-seize to stud threads going into head (not the nut side). Thread studs in by hand, then torque to specification using appropriate stud installation tool or double-nut method.
    Torque spec

    Exhaust Manifold Studs15 Nm (11 lb-ft)
13. 13

    Install new exhaust manifold gasket and manifold
    Position new exhaust manifold gasket onto cylinder head studs. Ensure gasket is oriented correctly with any alignment features. Carefully position exhaust manifold onto studs and gasket. Start all exhaust manifold nuts by hand to ensure proper thread engagement.
14. 14

    Torque exhaust manifold nuts
    Apply nickel-based anti-seize compound to exhaust manifold nut threads. Torque all manifold nuts to specification in a hot-to-cold pattern (center outward) using multiple passes. First pass at 50% torque, second pass at 100% torque. Verify all nuts are properly seated.
    Torque spec

    Exhaust Manifold Nuts30 Nm (22 lb-ft)
15. 15

    Reinstall turbocharger and remaining components
    Install new turbocharger-to-manifold gasket. Position turbocharger onto exhaust manifold and install mounting bolts with anti-seize. Torque to specification. Reconnect turbocharger oil feed and drain lines with new gaskets or seals. Reconnect turbocharger coolant lines. Reconnect downpipe to turbocharger outlet with new gasket, applying anti-seize to flange bolts before torquing. Install oxygen sensors with anti-seize on threads only (not sensor element). Reconnect EGR tube if equipped. Reinstall heat shields. Reinstall intake air system.
    Torque spec

    Heat Shield Bolts10 Nm (7 lb-ft)

Reassembly

1. Fill cooling system with Motorcraft Orange Coolant to proper level and bleed air from system
2. Verify all electrical connectors are properly seated and secured
3. Double-check all fasteners are torqued to specification before starting engine
4. Reinstall engine undershields and splash guards
5. Reconnect negative battery cable

Verification

• Start engine and listen for exhaust leaks at manifold-to-head and turbocharger connections
• Allow engine to reach operating temperature and inspect all connection points for leaks
• Check for coolant leaks at turbocharger coolant line connections
• Verify no oil leaks from turbocharger oil feed or drain connections
• Test drive vehicle and verify normal turbocharger boost operation with no abnormal noises
• Recheck exhaust manifold nut torque after first heat cycle (after engine cools)
• Scan for diagnostic trouble codes and verify no oxygen sensor or EGR codes present

Related trouble codes on this vehicle

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