Ford Full-Size Vans 1989-1996 Repair Guide

Intake Manifold

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REMOVAL & INSTALLATION



1989-93 4.9L Engine

The intake and exhaust manifolds on these engines are sometimes known as "combination manifolds" and are serviced as a unit. Typically, these manifolds are not referred to as a combination manifold, but since the lower intake and exhaust manifolds share the same bolts, and removal of either one requires removal of the other, we will refer to them as such. Refer to the Combination Manifold Removal & Installation procedure later in this section.

1994-96 4.9L Engine
UPPER INTAKE MANIFOLD

See Figure 1

  1. Disconnect the negative battery cable.
  2.  
  3. Tag and disengage the electrical connectors from the following components:

    EGR external pressure valve
     
    Throttle Position (TP) sensor
     
    Idle Air Control (IAC) valve
     
    EGR transducer
     

  4.  
  5. Tag and disengage the vacuum connections and hoses from the following components:

    EGR external pressure valve
     
    Evaporative emissions (EVAP) system hose from the throttle body and canister purge valve
     
    Vacuum lines to the upper intake manifold
     

  6.  
  7. Tag and disengage the EGR transducer hoses, unfasten the retaining screws, then remove the transducer and bracket.
  8.  
  9. Disconnect the PCV hose from the fitting on the underside of the manifold.
  10.  


CAUTION
When disconnecting the throttle cable ball stud, use a prytool close to the ball stud to pry it off. Never remove the cable by hand, as this may cause damage.

  1. Remove the throttle control splash shield.
  2.  
  3. Disconnect the throttle linkage and speed control actuator cable, position the loose cable out of the way.
  4.  
  5. Disconnect the air cleaner outlet tube from the throttle body.
  6.  
  7. Disconnect the EGR valve-to-exhaust manifold tube from the EGR external pressure valve and rear exhaust manifold.
  8.  
  9. Remove the EGR valve-to-exhaust manifold tube.
  10.  
  11. Remove the secondary air tube bypass assembly from the lower intake manifold as follows:
    1. Loosen the two retaining nuts.
    2.  
    3. Loosen the nut attaching the valve bracket to the lower intake manifold.
    4.  

  12.  
  13. If applicable, disconnect any other component that interferes with the removal.
  14.  
  15. Remove the screw and washer retaining the intake manifold support to the upper intake manifold.
  16.  
  17. Loosen the seven studs retaining the upper manifold.
  18.  
  19. Remove the upper manifold and throttle body as an assembly from the lower manifold.
  20.  



Click image to see an enlarged view

Fig. Fig. 1: Exploded view of the upper intake manifold assembly-1994-96 4.9L engine; 1996 model shown (others similar)

To install:
  1. Clean the mating surfaces as necessary and install a new gasket on the lower manifold half. Position the gasket correctly on the dowels.
  2.  
  3. Install the upper manifold onto the lower manifold, again using the dowels to locate the manifold halves together. Install the seven studs and hand tighten them.
  4.  
  5. Tighten the seven studs to 12-18 ft. lbs. (16-24 Nm).
  6.  
  7. Position the upper intake manifold support onto the boss of the upper intake located under the throttle body. install the screws, tightening them to 22-32 ft. lbs. (30-43 Nm).
  8.  
  9. Install the EGR valve-to-exhaust manifold tube between the external pressure valve and the rear exhaust manifold. The tube should be routed between the No. 5 and No. 6 lower intake runners, located under the throttle body.
  10.  
  11. Tighten both fittings to 25-35 ft. lbs. (34-47 Nm).
  12.  
  13. Connect the PCV hose to the fitting on the valve cover under the upper intake manifold plenum.
  14.  
  15. Install the secondary air bypass tube assembly onto the studs of the lower intake manifold. Tighten the nuts to 8-12 ft. lbs. (11-16 Nm).
  16.  
  17. Connect the accelerator cable, transmission kickdown cable and the speed control actuator, then install the splash shield.
  18.  
  19. Connect the air cleaner outlet tube to the throttle body.
  20.  
  21. Install the EGR transducer, tighten the retainers to 12-18 ft. lbs. (17-24 Nm) and connect the hoses.
  22.  
  23. Engage the vacuum connections and hoses to the following components:

    EGR external pressure valve
     
    Evaporative emissions (EVAP) system hose to the throttle body and canister purge valve
     
    Vacuum lines to the upper intake manifold
     

  24.  
  25. Engage the electrical connectors to the following components:

    EGR external pressure valve
     
    Throttle Position (TP) sensor
     
    Idle Air Control (IAC) valve
     
    EGR transducer
     

  26.  
  27. Connect the negative battery cable.
  28.  

LOWER INTAKE MANIFOLD

The lower intake manifold and exhaust manifolds for the 1994-96 4.9L engine must be removed together. To remove the lower intake manifold, refer to the appropriate Combination Manifold Removal & Installation procedure.

5.0L, 5.8L and 7.5L Engines

Discharge the fuel system pressure before starting any work that involves disconnecting fuel system lines. Refer to Fuel System .

UPPER INTAKE MANIFOLD

See Figures 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11

  1. Disconnect the negative battery cable.
  2.  
  3. Remove the air cleaner assembly from the upper intake manifold.
  4.  


CAUTION
When draining the coolant, keep in mind that cats and dogs are attracted by ethylene glycol antifreeze and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

  1. Drain the cooling system.
  2.  
  3. Disengage the electrical connectors at the idle air control valve, throttle position sensor and EGR position sensor.
  4.  



Click image to see an enlarged view

Fig. Fig. 2: Exploded view of the intake manifold assembly-1994-95 5.0 and 5.8L engines



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Fig. Fig. 3: Exploded view of the intake manifold assembly-1996 5.0 and 5.8L engines



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Fig. Fig. 4: Intake manifold assembly-7.5L engines

  1. Disconnect the throttle linkage at the throttle ball and the transmission linkage from the throttle body.
  2.  
  3. Loosen the bolts that secure the bracket to the intake and position the bracket and cables out of the way.
  4.  
  5. Tag and disengage the upper manifold vacuum fitting connections by removing all the vacuum lines at the vacuum tree (label lines for position identification).
  6.  



Click image to see an enlarged view

Fig. Fig. 5: Disconnect the vacuum lines at the vacuum tree



Click image to see an enlarged view

Fig. Fig. 6: Tag and disconnect the hoses from the top of the upper intake manifold

  1. Disconnect the vacuum lines to the EGR external pressure valve and fuel pressure regulator.
  2.  
  3. Disconnect the PCV system by disconnecting the hose from the fitting at the rear of the upper manifold.
  4.  
  5. Disconnect the oil filler pipe.
  6.  
  7. If necessary, remove the EGR transducer by loosening the retainers and disengaging it from the bracket.
  8.  
  9. If equipped, disconnect the two canister purge lines from the fittings at the throttle body.
  10.  
  11. Place a suitable container under the van and disconnect the water heater lines from the throttle body.
  12.  
  13. Disconnect the EGR tube from the EGR external pressure valve by loosening the flange nut.
  14.  
  15. If applicable, disconnect any other component that interferes with the removal.
  16.  
  17. Remove the bolt from the upper intake support bracket to upper manifold.
  18.  

On some 5.0L engines it may be necessary to remove the intake manifold shield before removing the upper intake manifold assembly.

  1. Loosen the upper manifold retaining bolts and remove the upper intake manifold and throttle body as an assembly.
  2.  
  3. Clean and inspect all mounting surfaces of the upper and lower intake manifolds.
  4.  



Click image to see an enlarged view

Fig. Fig. 7: Unfasten the upper intake manifold center mounting bolts ...



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Fig. Fig. 8: ... and the lower mounting bolts



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Fig. Fig. 9: Lift the upper intake manifold up so that it clears the hoses, pipes and other obstructions ...



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Fig. Fig. 10: ... then remove the manifold from the engine compartment



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Fig. Fig. 11: Remove the upper intake manifold gasket from the lower intake manifold

To install:
  1. Position a new mounting gasket on the lower intake manifold.
  2.  
  3. Install the intake manifold shield on the 5.0L models, if applicable.
  4.  
  5. If the EGR transducer was removed, tighten the retainers to 9-12 ft. lbs. (12-16 Nm) on the 5.0L and 12-18 ft. lbs. (17-24 Nm) on 5.8L engines.
  6.  
  7. Install the upper intake manifold and throttle body as an assembly. Install the upper manifold retaining bolts and install the bolt at the upper intake support bracket. Mounting bolts are tightened to 12-18 ft. lbs. (16-24 Nm).
  8.  
  9. Install the lower intake support bracket to the upper manifold attaching bolt.
  10.  
  11. Connect the EGR tube at the EGR valve.
  12.  
  13. Install the two canister purge lines at the fittings at the throttle body.
  14.  
  15. Connect the PCV system hose at the fitting at the rear of the upper manifold.
  16.  
  17. Connect the upper manifold vacuum lines at the vacuum tree. Install the vacuum lines at the EGR valve and fuel pressure regulator.
  18.  
  19. Install the throttle bracket on the intake manifold. Connect the throttle linkage and the transmission linkage at the throttle body.
  20.  
  21. Engage the electrical connectors at the air bypass valve, throttle position sensor and EGR position sensor.
  22.  
  23. Install the air cleaner.
  24.  
  25. Connect the negative battery cable.
  26.  

LOWER INTAKE MANIFOLD

See Figures 12, 13, 14, 15, 16, 17, 18, 19 and 20

  1. Remove the upper manifold and throttle body.
  2.  


CAUTION
When draining the coolant, keep in mind that cats and dogs are attracted by ethylene glycol antifreeze and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

  1. Drain the cooling system.
  2.  
  3. Remove the distributor assembly, cap and wires.
  4.  
  5. Disengage the electrical connectors at the engine as applicable, including the Engine Coolant Temperature (ECT) sensor, engine temperature sending unit, Air Charge Temperature (ACT) sensor, Intake Air Temperature (IAT) sensor, Electrical Vacuum Regulator (EVR), thermactor solenoids and Knock Sensor (KS).
  6.  
  7. If equipped, disengage the radio interference capacitor.
  8.  
  9. If equipped, disengage the electrical connector and vacuum harness from the EGR regulator solenoid.
  10.  
  11. If equipped, disengage the electrical connector and vacuum harness from the secondary air injection vacuum regulator solenoid.
  12.  



Click image to see an enlarged view

Fig. Fig. 12: Lower intake manifold assembly-5.0L and 5.8L MFI engines

  1. Disconnect the injector wiring harness from the main harness assembly.
  2.  
  3. If necessary, remove the wiring harness retainers and move the harness aside for clearance.
  4.  



Click image to see an enlarged view

Fig. Fig. 13: Unfasten the wiring harness retainers



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Fig. Fig. 14: Move the wiring harness aside to gain access to the manifold bolts

  1. Remove the oxygen sensor ground wire from the intake manifold stud.
  2.  

The ground wire must be installed at the same position it was removed from.

  1. Relieve the fuel system pressure.
  2.  
  3. Disconnect the fuel supply and return lines from the fuel rails.
  4.  
  5. Remove the upper radiator hose from the thermostat housing.
  6.  
  7. Remove the water bypass hose.
  8.  
  9. Remove the heater outlet hose at the intake manifold.
  10.  
  11. Loosen the coil bracket retaining nut and set the bracket assembly aside.
  12.  
  13. Loosen the intake manifold mounting bolts and studs. Pay attention to the location of the bolts and studs for reinstallation.
  14.  
  15. Remove the lower intake manifold assembly.
  16.  



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Fig. Fig. 15: Loosen the lower intake manifold retaining bolts and studs



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Fig. Fig. 16: Remove the lower intake manifold from the engine assembly



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Fig. Fig. 17: Use a scraper to remove any gasket material left on the mating surfaces

To install:
  1. Clean and inspect the mounting surfaces of the heads and manifold.
  2.  
  3. Apply a 1 / 16 in. (1.5mm) bead of RTV sealer to the ends of the manifold seal (the junction point of the seals and gaskets).
  4.  

The gaskets must be interlocked with the seal tabs
  1. Install the end seals and intake gaskets on the cylinder heads.
  2.  
  3. Install locator pins at opposite ends of each head and carefully lower the intake manifold into position.
  4.  
  5. On 1989-93 models, install and tighten the mounting bolts and studs to 23-25 ft. lbs. (32-33 Nm) in the sequence illustrated. Wait ten minutes and retighten the retainers to the same specification.
  6.  



Click image to see an enlarged view

Fig. Fig. 18: Lower intake manifold tightening sequence-5.0L and 5.8L EFI engines



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Fig. Fig. 19: Lower intake manifold torque sequence-5.0L and 5.8L MFI engines



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Fig. Fig. 20: Lower intake manifold tightening sequence-7.5L engines

  1. On 1994-95 models, install and tighten the mounting bolts and studs in the sequence illustrated and in the following steps:
    1. First pass: 8 ft. lbs. (11 Nm)
    2.  
    3. Second pass: 16 ft. lbs. (22 Nm)
    4.  
    5. Final pass: 23-25 ft. lbs. (31-34 Nm)
    6.  

  2.  
  3. On 1996 models, install and tighten the mounting bolts and studs in the sequence illustrated and in the following steps:
    1. First pass: 5-10 ft. lbs. (7-14 Nm)
    2.  
    3. Final pass: 23-25 ft. lbs. (31-34 Nm)
    4.  

  4.  
  5. Install the coil mounting bracket.
  6.  
  7. Install the upper radiator hose and water bypass tube or hose.
  8.  
  9. Install the heater outlet hose at the intake manifold.
  10.  
  11. Connect the fuel supply and return lines at the fuel rails.
  12.  
  13. Connect the injector wiring harness from the main harness assembly. Install the ground wire from the intake manifold stud.
  14.  
  15. Engage the applicable electrical connectors and vacuum hoses to the engine's sensors, sending units and solenoids.
  16.  
  17. Engage the radio ignition interference capacitor connector.
  18.  
  19. Install the distributor assembly, cap and wires.
  20.  
  21. Fill the cooling system.
  22.  

7.3L Diesel Engines
1989-94 MODELS

See Figures 21 and 22

  1. Disconnect both negative battery cables.
  2.  
  3. Remove the engine cover.
  4.  
  5. Remove the air cleaner and install clean rags into the air intake of the intake manifold. It is important that no dirt or foreign objects get into the diesel intake.
  6.  
  7. Disconnect the fuel inlet and return lines from the fuel filter.
  8.  
  9. Loosen the fuel filter attaching bolts, then remove the filter and bracket assembly.
  10.  
  11. Remove the injection pump as described in Fuel System under Diesel Fuel System.
  12.  
  13. Tag and disengage the glow plug harness and the controller.
  14.  
  15. Label the positions of the wires and remove the engine wiring harness from the engine.
  16.  

The engine harness ground cables must be removed from the back of the left cylinder head.

  1. If applicable, disconnect any other component that interferes with the removal.
  2.  
  3. Remove the bolts attaching the intake manifold to the cylinder heads and remove the manifold.
  4.  
  5. Remove the CDR tube grommet from the valley pan.
  6.  
  7. Remove the bolts attaching the valley pan strap to the front of the engine block and remove the strap.
  8.  
  9. Remove the valley pan drain plug and remove the valley pan.
  10.  

To install:
  1. Clean all the mating surfaces.
  2.  
  3. Apply a 1 / 8 in. (3mm) bead of RTV sealer to each end of the cylinder block as shown in the accompanying illustration.
  4.  



Click image to see an enlarged view

Fig. Fig. 21: Apply sealer to the diesel cylinder block-to-intake manifold mating surfaces on each end

The RTV sealer should be applied immediately prior to the valley pan installation.

  1. Install the valley pan drain plug, CDR tube and new grommet into the valley pan.
  2.  
  3. Install a new O-ring and new back-up ring on the CDR valve.
  4.  
  5. Install the valley pan strap on the front of the valley pan.
  6.  
  7. Install the intake manifold and tighten the bolts to 24 ft. lbs. (32 Nm) using the sequence shown in the illustration.
  8.  



Click image to see an enlarged view

Fig. Fig. 22: Diesel engine intake manifold bolt tightening sequence-1989-94 engines

  1. Reconnect the engine wiring harness and the engine ground wire located to the rear of the left cylinder head.
  2.  
  3. Install the glow plug controller and wiring.
  4.  
  5. Install the injection pump using the procedure outlined in Fuel System under Diesel Fuel System.
  6.  
  7. Install the fuel filter and bracket, then tighten the retainers to 24-39 ft. lbs. (33-52 Nm).
  8.  
  9. Connect the fuel return and inlet lines.
  10.  
  11. Remove the rag from the intake manifold and replace the air cleaner. Connect both negative battery cables to both batteries.
  12.  
  13. Run the engine and check for oil and fuel leaks.
  14.  

If necessary, purge the nozzle high pressure lines of air by loosening the connector one half to one turn and cranking the engine until solid stream of fuel, devoid of any bubbles, flows from the connection.


CAUTION
Keep eyes and hands away from the nozzle spray. Fuel spraying from the nozzle under high pressure can penetrate the skin.

  1. Check and adjust the injection pump timing, as described in Fuel System under Diesel Fuel System.
  2.  

1995-96 MODELS

See Figure 23

Click image to see an enlarged view

Fig. Fig. 23: Loosen the clamps and disconnect the compressor manifold and intake manifold hoses

  1. Loosen the intake manifold hose clamps and the clamp retaining the compressor manifold to the turbocharger.
  2.  
  3. On the left cylinder head it may be necessary to remove the turbocharger.
  4.  
  5. Remove the compressor manifold.
  6.  
  7. Loosen the clamps and remove the intake manifold hoses.
  8.  
  9. Loosen the intake manifold cover retainers and remove the covers.
  10.  
  11. Installation is the reverse of removal. Tighten the intake manifold cover bolts to 18 ft. lbs. (24 Nm).
  12.  

 
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