GM Full Size Vans 1987-1997 Repair Guide

Lower Intake Manifold

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REMOVAL & INSTALLATION



4.3L Engines
1987-95 MODELS

See Figures 1, 2 and 3

  1. Disconnect the negative battery cable. Drain the cooling system.
  2.  



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Fig. Fig. 1: Disconnect all lines, hoses ...:



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Fig. Fig. 2: ... and wiring from the intake manifold or from manifold mounted support brackets



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Fig. Fig. 3: A ratchet with various extensions will be very helpful for manifold bolt removal

  1. Remove the engine cover.
  2.  
  3. Remove the air cleaner assembly.
  4.  

Mark the relationship of the distributor and rotor for proper reassembly

  1. Remove the distributor.
  2.  
  3. Disconnect the accelerator and cruise control cables with their brackets.
  4.  
  5. Remove the cruise control transducer (if equipped).
  6.  
  7. Remove the air conditioner compressor without disconnecting the lines and set it aside.
  8.  
  9. Remove the alternator bracket and the idler pulley bracket at the manifold.
  10.  
  11. Disconnect all electrical connections and vacuum lines from the manifold. Remove the EGR valve if necessary.
  12.  
  13. Disconnect the fuel line at the intake manifold.
  14.  
  15. Remove the heater pipe.
  16.  
  17. Disconnect the upper radiator hose and pull it off.
  18.  
  19. Tag and disconnect the power brake vacuum pipe and the EGR vacuum line.
  20.  
  21. Tag and disconnect the coil wires and if necessary remove the coil.
  22.  
  23. Remove the sensors and bracket on the right side. Disconnect the wiring harness on the right side and position it out of the way.
  24.  
  25. If equipped, disconnect the transmission dipstick tube.
  26.  

Mark the location of the intake manifold studs for proper reassembly

  1. Remove the intake manifold bolts. Remove the manifold and the gaskets. Remember to reinstall the O-ring between the intake manifold and timing chain cover during assembly, if so equipped.
  2.  

See Figures 4, 5, 6 and 7



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Fig. Fig. 4: Loosen and remove the intake manifold retaining bolts ...



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Fig. Fig. 5: ... then remove the manifold - the carburetor (or TBI unit) need not be removed



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Fig. Fig. 6: Once the manifold has been removed, you have free access to the lifter valley:



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Fig. Fig. 7: To keep debris out of the engine, cover all openings before cleaning the gasket surfaces:

To install:

Before installing the intake manifold, be sure that the gasket surfaces are thoroughly clean.

  1. Use plastic gasket retainers to prevent the manifold gasket from slipping out of place, if so equipped. Coat the front and rear sealing surfaces with a 0.19 in. (5mm) bead of RTV sealant. Extend the bead approximately 1 / 2 in. (13mm) down each head to help retain the gaskets.
  2.  
  3. Install the manifold and the gaskets. Remember to reinstall the O-ring between the intake manifold and timing chain cover, if so equipped.
  4.  
  5. Install the intake manifold bolts and tighten them to 35 ft. lbs. (48 Nm) in the sequence shown. On the final tightening sequence tighten bolt #9 to 41 ft. lbs. (56 Nm).
  6.  
  7. Connect the transmission dipstick tube, if removed.
  8.  
  9. Connect the coil wires. Install the sensors and bracket on the right side. Connect the wiring harness.
  10.  
  11. Connect the power brake vacuum pipe and the EGR vacuum line.
  12.  
  13. Connect the upper radiator hose.
  14.  
  15. Install the heater pipe.
  16.  
  17. Connect the fuel line(s).
  18.  
  19. Connect all electrical connections and vacuum lines at the manifold. Install the EGR valve.
  20.  
  21. Install the rear air conditioner compressor.
  22.  
  23. Install the alternator bracket and the idler pulley bracket at the manifold.
  24.  
  25. If equipped, install the cruise control transducer.
  26.  
  27. Connect the accelerator and cruise control cables with their brackets.
  28.  
  29. Install the distributor.
  30.  
  31. Install the air cleaner assembly.
  32.  
  33. Install the engine cover.
  34.  
  35. Fill the cooling system.
  36.  

See Figures 8, 9 and 10



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Fig. Fig. 8: Intake manifold - 4.3L engines



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Fig. Fig. 9: Intake manifold bolt tightening sequence - 1987-91 4.3L engine



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Fig. Fig. 10: Intake manifold bolt tightening sequence - 1992-95 4.3L engine

1996-97 MODELS

See Figure 11



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Fig. Fig. 11: Intake manifold bolt tightening sequence - 1996-97 4.3L engine

  1. Remove the upper intake manifold using the recommended procedure outlined in this section.
  2.  
  3. Remove the distributor.
  4.  
  5. Disconnect the upper radiator hose from the thermostat housing.
  6.  
  7. Disconnect the heater hose from the lower intake manifold.
  8.  
  9. Remove the coolant bypass hose.
  10.  
  11. Remove the EGR valve.
  12.  
  13. Disconnect the fuel pressure and return lines from the lower intake manifold.
  14.  
  15. Disconnect the wiring harnesses and brackets from the lower manifold.
  16.  
  17. Disconnect the accelerator and cruise control cables with their brackets.
  18.  
  19. Remove the transmission oil level indicator and tube, if equipped.
  20.  
  21. Remove the ignition coil and bracket.
  22.  
  23. Remove the EGR tube, clamp and bolt.
  24.  
  25. Remove the PCV valve and hose.
  26.  
  27. Remove the A/C compressor and bracket, but do NOT disconnect the lines. Move the compressor out of the way. Take care not to kink the A/C lines.
  28.  
  29. Loosen the compressor mounting bracket and slide it forward, but do NOT remove it.
  30.  
  31. Remove the lower intake manifold bolts.
  32.  
  33. Remove the lower intake manifold.
  34.  

To install:
  1. Clean all gasket surfaces completely.
  2.  
  3. Install the intake manifold gaskets with the port blocking plates facing the rear. Factory gaskets should have the words "This Side Up" visible.
  4.  
  5. Apply gasket sealer to the front and rear sealing surfaces of the engine block. Extend the sealer approximately 1 / 2 -inch (13mm) onto the heads.
  6.  
  7. Install the lower intake manifold.
  8.  
  9. Apply sealer to the lower intake manifold bolts prior to installation.
  10.  
  11. Install the bolts and tighten in sequence and in 3 steps as follows:
    1. First step to 26 inch lbs. (3 Nm).
    2.  
    3. Second step to 106 inch lbs. (12 Nm).
    4.  
    5. Final step to 11 ft. lbs. (15 Nm).
    6.  

  12.  
  13. Install the PCV valve and hose.
  14.  
  15. Install the EGR tube, clamp and bolt.
  16.  
  17. Install the ignition coil and bracket.
  18.  
  19. Install the transmission oil level indicator and tube, if equipped.
  20.  
  21. Connect the wiring harnesses and brackets to the lower manifold.
  22.  
  23. Connect the fuel pressure and return lines to the lower intake manifold.
  24.  
  25. Install the EGR valve.
  26.  
  27. Install the coolant bypass hose.
  28.  
  29. Connect the heater hose to the lower intake manifold.
  30.  
  31. Connect the upper radiator hose to the thermostat housing.
  32.  
  33. Disconnect the accelerator and cruise control cables with their brackets.
  34.  
  35. Install the EGR tube.
  36.  
  37. Install the A/C compressor and bracket.
  38.  
  39. Install the distributor.
  40.  
  41. Connect the negative battery cable.
  42.  
  43. Start the vehicle and check the ignition timing (not adjustable).
  44.  
  45. Verify no oil, coolant, vacuum or fuel leaks.
  46.  

5.0L and 5.7L Engines
1987-95 MODELS

See Figures 12 and 13

  1. Disconnect the negative battery cable. Drain the cooling system.
  2.  
  3. Remove the engine cover.
  4.  
  5. Remove the air cleaner assembly.
  6.  
  7. If necessary, remove the coolant recovery reservoir.
  8.  



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Fig. Fig. 12: Intake manifold - 5.0L and 5.7L engines



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Fig. Fig. 13: Intake manifold bolt tightening sequence - 1987-95 5.0L and 5.7L engines

  1. Remove the upper radiator hose from the thermostat housing.
  2.  
  3. Disconnect the heater pipe at the rear of the manifold.
  4.  
  5. Disconnect the rear alternator brace at the manifold.
  6.  
  7. Disengage all electrical connections and vacuum lines from the manifold. Remove the EGR valve if necessary.
  8.  

Mark the relationship of the distributor and rotor for proper reassembly

  1. Remove the distributor.
  2.  
  3. Disconnect the fuel line at the intake manifold.
  4.  
  5. Remove the accelerator and cruise control linkage.
  6.  
  7. Remove the air conditioner compressor rear bracket.
  8.  
  9. Remove the brake booster vacuum pipe and then disconnect the coil wires.
  10.  
  11. Remove the emission control sensors and their bracket from the right side.
  12.  
  13. Remove the fuel line bracket at the rear of the manifold and position the fuel lines out of the way.
  14.  
  15. Remove the bracket behind the idler pulley.
  16.  
  17. Remove the carburetor or TBI unit if necessary. Refer to Fuel System for this procedure.
  18.  

Mark the location of the intake manifold studs for proper reassembly

  1. Remove the intake manifold bolts. Remove the manifold and the gaskets. Remember to reinstall the O-ring between the intake manifold and timing chain cover during assembly, if so equipped.
  2.  

see Figures 14, 15 and 16



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Fig. Fig. 14: Remove the intake manifold retaining bolts



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Fig. Fig. 15: Remove the intake manifold



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Fig. Fig. 16: Using a scraper clean the intake manifold gasket mating surfaces

To install:

Before installing the intake manifold, be sure that the gasket surfaces are thoroughly clean.

  1. Use plastic gasket retainers to prevent the manifold gasket from slipping out of place, if so equipped. Place a 3 / 16 in. (5mm) bead of RTV type silicone sealer on the front and rear ridges of the cylinder block-to-manifold mating surfaces. Extend the bead 1 / 2 in. (13mm) up each cylinder head to seal and retain the manifold side gaskets.
  2.  
  3. Install the manifold and the gaskets. Remember to reinstall the O-ring between the intake manifold and timing chain cover, if so equipped.
  4.  
  5. Install the intake manifold bolts and tighten in the proper sequence. Tighten to 35 ft. lbs. (48Nm).
  6.  
  7. Install the carburetor or TBI unit if removed. Refer to Fuel System for this procedure.
  8.  
  9. Install the bracket behind the idler pulley.
  10.  
  11. Install the fuel line bracket at the rear of the manifold.
  12.  
  13. Install the emission control sensors and their bracket on the right side.
  14.  
  15. Install the brake booster vacuum pipe and then connect the coil wires.
  16.  
  17. Install the air conditioner compressor rear bracket.
  18.  
  19. Install the accelerator and cruise control linkage.
  20.  
  21. Install the fuel line and bracket.
  22.  
  23. Install the distributor.
  24.  
  25. Engage all electrical connections and vacuum lines at the manifold. Install the EGR valve.
  26.  
  27. Connect the rear alternator brace at the manifold.
  28.  
  29. Connect the heater pipe to the rear of the manifold.
  30.  
  31. Install the upper radiator hose.
  32.  
  33. If removed, install the coolant recovery reservoir.
  34.  
  35. Install the air cleaner assembly.
  36.  
  37. Connect the negative battery cable. Fill the cooling system.
  38.  

1996-97 MODELS

See Figure 17



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Fig. Fig. 17: Intake manifold bolt tightening sequence - 1996-97 5.0L and 5.7L engines

  1. Remove the upper intake manifold using the recommended procedure outlined in this section.
  2.  
  3. Remove the distributor.
  4.  
  5. Disconnect the upper radiator hose from the thermostat housing.
  6.  
  7. Disconnect the heater hose from the lower intake manifold.
  8.  
  9. Remove the coolant bypass hose.
  10.  
  11. Remove the EGR valve.
  12.  
  13. Disconnect the fuel pressure and return lines from the lower intake manifold.
  14.  
  15. Disconnect the wiring harnesses and brackets from the lower manifold.
  16.  
  17. Remove the left side valve cover.
  18.  
  19. Remove the transmission oil level indicator and tube, if equipped.
  20.  
  21. Remove the EGR tube, clamp and bolt.
  22.  
  23. Remove the PCV valve and hose.
  24.  
  25. Remove the A/C compressor and bracket, but do NOT disconnect the lines. Move the compressor out of the way. Take care not to kink the A/C lines.
  26.  
  27. Loosen the compressor mounting bracket and slide it forward, but do NOT remove it.
  28.  
  29. Remove the power brake vacuum tube.
  30.  
  31. Remove the lower intake manifold bolts.
  32.  
  33. Remove the lower intake manifold.
  34.  

To install:
  1. Clean all gasket surfaces completely.
  2.  
  3. Install the intake manifold gaskets with the port blocking plates facing the rear. Factory gaskets should have the words "This Side Up" visible.
  4.  
  5. Apply gasket sealer to the front and rear sealing surfaces of the engine block. Extend the sealer approximately 1 / 2 -inch (13mm) onto the heads.
  6.  
  7. Install the lower intake manifold.
  8.  
  9. Apply sealer to the lower intake manifold bolts prior to installation.
  10.  
  11. Install the bolts and tighten in sequence and in 3 steps as follows:
    1. First step to 71 inch lbs. (8 Nm).
    2.  
    3. Second step to 106 inch lbs. (12 Nm).
    4.  
    5. Final step to 11 ft. lbs. (15 Nm).
    6.  

  12.  
  13. Install the power brake vacuum tube.
  14.  
  15. Install the PCV valve and hose.
  16.  
  17. Install the EGR tube, clamp and bolt.
  18.  
  19. Install the transmission oil level indicator and tube, if equipped.
  20.  
  21. Install the left side valve cover.
  22.  
  23. Connect the wiring harnesses and brackets to the lower manifold.
  24.  
  25. Connect the fuel pressure and return lines to the lower intake manifold.
  26.  
  27. Install the EGR valve.
  28.  
  29. Install the coolant bypass hose.
  30.  
  31. Connect the heater hose to the lower intake manifold.
  32.  
  33. Connect the upper radiator hose to the thermostat housing.
  34.  
  35. Install the A/C compressor and bracket.
  36.  
  37. Install the distributor.
  38.  
  39. Connect the negative battery cable.
  40.  
  41. Start the vehicle and check the ignition timing (not adjustable).
  42.  
  43. Verify no oil, coolant, vacuum or fuel leaks.
  44.  

6.2L Diesel Engine

See Figure 18

  1. Disconnect both batteries.
  2.  
  3. Remove the engine cover.
  4.  



Click image to see an enlarged view

Fig. Fig. 18: Intake manifold bolt tightening sequence - 6.2L diesel engine (1987-95 6.5L engine similar)

  1. Remove the air cleaner assembly and, if applicable, the air intake duct.
  2.  
  3. Remove the crankcase ventilator tubes, and disconnect the secondary fuel filter lines. Remove the secondary filter and adapter.
  4.  
  5. Remove the thermostat bolts and the upper radiator hose.
  6.  
  7. Loosen the vacuum pump hold-down clamp and rotate the pump to gain access to the nearest manifold bolt.
  8.  
  9. Remove the EPR/EGR boost solenoids and bracket, if equipped. Tag and disconnect the EGR and crankcase vent hoses.
  10.  
  11. Remove the heater hose bracket, tag and disconnect any vacuum lines and electrical connections as necessary.
  12.  
  13. If equipped with a turbocharger remove the long pencil brace.
  14.  
  15. Remove the fuel line brackets and ground straps.
  16.  
  17. Remove the rear air conditioning bracket, if equipped.
  18.  
  19. Remove the intake manifold bolts. The injection line clips are retained by these bolts.
  20.  
  21. Remove the intake manifold.
  22.  

If the engine is to be further serviced with the manifold removed, install protective covers over the intake ports.

To install:
  1. Clean the manifold gasket surfaces on the cylinder heads and install new gaskets before installing the manifold.
  2.  

The gaskets have an opening for the EGR valve on light duty installations. An insert covers this opening on heavy duty installations.

  1. Install the manifold. Tighten the bolts in the sequence illustrated to 32 ft. lbs. (42 Nm).
  2.  
  3. The secondary filter must be filled with clean diesel fuel before it is reinstalled.
  4.  
  5. Install the rear air conditioning bracket, if equipped.
  6.  
  7. Install the ground straps and fuel line brackets.
  8.  
  9. Install the turbocharger pencil brace, if equipped.
  10.  
  11. Engage any electrical connections and vacuum hoses that were removed.
  12.  
  13. Install the EPR/EGR valve bracket. Reconnect the hoses.
  14.  
  15. Tighten the vacuum pump hold-down clamp.
  16.  
  17. Install the upper radiator hose and the thermostat bolts.
  18.  
  19. Install the secondary filter and adapter.
  20.  
  21. Connect the secondary fuel filter lines.
  22.  
  23. Install the crankcase ventilator tubes.
  24.  
  25. Install the air cleaner assembly.
  26.  
  27. Connect both batteries.
  28.  

6.5L Diesel Engine

See Figures 19



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Fig. Fig. 19: Exploded view of the intake manifold mounting - 1996-97 6.5L diesel engine

  1. Have the A/C system discharged by a qualified technician using approved equipment.
  2.  
  3. Disconnect both batteries.
  4.  
  5. Remove the engine cover.
  6.  
  7. Remove the air cleaner assembly and if applicable the air intake duct.
  8.  
  9. Remove the Crankcase Depression Regulator (CDR) vent hose.
  10.  
  11. Disconnect the fuel lines and brackets.
  12.  
  13. Remove the wiring harness and all connections and brackets.
  14.  
  15. Remove the oil and transmission dipstick tubes.
  16.  
  17. Remove the rear A/C line.
  18.  


WARNING
Do not attempt to remove center intake manifold with the with the left and right intake manifolds as an assembly as this may damage the gaskets, turbocharger and center intake manifold during reassembly.

  1. Remove the center Intake manifold.
  2.  
  3. Remove the upper intake manifold.
  4.  
  5. Remove the glow plug relay.
  6.  
  7. Tag the fuel line clips, lower intake manifold studs and brackets before removal to aid during installation.
  8.  
  9. Loosen the manifold studs and fuel line clips, then remove the lower manifold and gaskets.
  10.  

If the engine is to be further serviced with the manifold removed, install protective covers over the intake ports.

To install:

See Figure 20

  1. Clean the manifold gasket surfaces on the cylinder heads and install new gaskets before installing the manifold.
  2.  
  3. Install the lower manifold. Apply Teflon sealer to the bolts and tighten them in the sequence illustrated to 31 ft. lbs. (42 Nm).
  4.  
  5. Install the center intake manifold.
  6.  
  7. Install the ground straps and fuel line brackets.
  8.  
  9. Engage any electrical connections and vacuum hoses that were removed.
  10.  
  11. Install the engine oil and transmission dipstick tubes.
  12.  
  13. Install the CDR vent hose.
  14.  

Always install anew O-ring between the upper manifold and turbocharger. Coat the O-ring with clean engine oil before installation.

  1. Install the upper manifold and tighten the bolts to 17 ft. lbs. (23 Nm).
  2.  
  3. Connect the A/C lines and have the system recharged by a qualified technician using approved equipment.
  4.  
  5. Install the glow plug relay.
  6.  
  7. Install the air cleaner assembly.
  8.  
  9. Install the engine cover.
  10.  
  11. Connect both batteries.
  12.  

CENTER INTAKE MANIFOLD

See Figure 21



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Fig. Fig. 21: Center intake manifold mounting - 1996-97 models

  1. Disconnect the negative battery cable and remove the engine cover.
  2.  
  3. Loosen the center intake manifold bolts and remove the manifold.
  4.  

To install:

Install a new O-ring lubricated with clean engine oil between the manifold and the turbocharger

  1. Install the manifold and tighten the bolts to 17 ft. lbs. (23 Nm).
  2.  
  3. Install the engine cover and connect the negative battery cable.
  4.  

7.4L Engines
1987-95 MODELS
  1. Disconnect the battery.
  2.  
  3. Remove the engine cover.
  4.  


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

  1. Drain the cooling system.
  2.  
  3. Remove the air cleaner assembly.
  4.  
  5. Remove the upper radiator hose, thermostat housing and the bypass hose, if necessary.
  6.  
  7. Disconnect the heater hose and pipe.
  8.  
  9. Tag and disconnect all electrical connections and vacuum lines from the manifold and move them to the side.
  10.  
  11. Disconnect the accelerator linkage.
  12.  
  13. Disconnect the cruise control cable, if equipped.
  14.  
  15. Disconnect the TVS cable.
  16.  
  17. Remove the fuel line at the manifold.
  18.  
  19. Remove the TBI unit, if necessary. Refer to Fuel System for this procedure.
  20.  

Mark the relationship of the distributor and rotor for proper reassembly

  1. Remove the distributor, if necessary.
  2.  
  3. Remove the cruise control transducer, if equipped.
  4.  
  5. Disconnect the ignition coil wires and remove the coil if necessary.
  6.  
  7. Remove the EGR solenoid and bracket.
  8.  
  9. Remove the MAP sensor and bracket.
  10.  
  11. Remove the air conditioning compressor.
  12.  
  13. Remove the front alternator/AIR pump bracket, if necessary.
  14.  
  15. Remove the intake manifold bolts.
  16.  
  17. Remove the manifold and the gaskets and seals.
  18.  

Remember to reinstall the O-ring between the intake manifold and timing chain cover during assembly, if so equipped.

To install:

Before installing the intake manifold, be sure that the gasket surfaces are thoroughly clean.

See Figures 22, 23 and 24

  1. Install the manifold and the gaskets and seals.
  2.  



Click image to see an enlarged view

Fig. Fig. 22: Intake manifold bolt tightening sequence - 1987-90 7.4L engines



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Fig. Fig. 23: Intake manifold bolt tightening sequence - 1991-94 7.4L engine



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Fig. Fig. 24: Intake manifold bolt tightening sequence - 1995 7.4L engine

  1. Install the intake manifold bolts. Tighten the bolts to 30 ft. lbs. (40 Nm) in the proper sequence.
  2.  
  3. Install the front alternator/AIR pump bracket, if removed.
  4.  
  5. Install the air conditioning compressor rear bracket, if removed.
  6.  
  7. Install the MAP sensor and bracket.
  8.  
  9. Install the EGR solenoid and bracket.
  10.  
  11. Connect the ignition coil wires.
  12.  
  13. Install the cruise control transducer, if equipped.
  14.  
  15. Install the distributor.
  16.  
  17. Install the TBI unit, if removed. Refer to Fuel System for this procedure.
  18.  
  19. Install the fuel line at the manifold.
  20.  
  21. Connect the TVS cable.
  22.  
  23. Connect the cruise control cable, if equipped.
  24.  
  25. Connect the accelerator linkage.
  26.  
  27. Connect all electrical connections and vacuum lines at the manifold.
  28.  
  29. Connect the heater hose and pipe.
  30.  
  31. Install the upper radiator hose, thermostat housing and the bypass hose.
  32.  
  33. Install the air cleaner assembly.
  34.  
  35. Fill the cooling system.
  36.  
  37. Install the engine cover.
  38.  
  39. Connect the battery.
  40.  

1996-97 MODELS
  1. Have the A/C system discharged. Recover the refrigerant using the appropriate recycling equipment.
  2.  
  3. Remove the upper intake manifold using the recommended procedure outlined in this section.
  4.  
  5. Remove the A/C lines at the compressor.
  6.  
  7. Remove the distributor using the recommended procedure. Mark the relationship of the distributor housing and rotor for proper reassembly.
  8.  
  9. Drain the engine coolant. Remove the upper radiator hose at the thermostat housing.
  10.  
  11. Disconnect the heater hose from the manifold.
  12.  
  13. Disconnect the fuel line brackets and rail.
  14.  
  15. Disconnect the water pump bypass hose.
  16.  
  17. Remove the lower intake manifold bolts and remove the lower intake manifold and gaskets.
  18.  

To install:
  1. Clean all parts well:
    1. Clean all traces of gasket from the sealing surfaces.
    2.  
    3. Inspect for cracks, broken flanges and gasket surface damage.
    4.  
    5. Clean excessive carbon buildup in the exhaust passages.
    6.  
    7. Clean scale and deposits from the coolant passages.
    8.  
    9. Clean the EGR passage of carbon deposits.
    10.  

  2.  
  3. Install the gaskets to the cylinder head in their proper position. Factory-type gaskets should be stamped "This Side Up".
  4.  
  5. Install the front and rear intake manifold seals to the block.
  6.  
  7. Apply a 3 / 16 -inch (5mm) bead of RTV GM #1052289, or equivalent, to the four seal corners of the block. Extend the bead approximately 1 / 2 -inch (13mm) up the cylinder head to seal and retain the gaskets.
  8.  
  9. Carefully place the lower intake manifold into position on the engine.
  10.  
  11. Apply sealer, GM #1052080, or equivalent, to the lower intake manifold bolts. Install the lower manifold bolts and tighten them in sequence to 30 ft. lbs. (40 Nm).
  12.  
  13. Install the water pump bypass hose.
  14.  
  15. Install the wiring harness connectors and brackets.
  16.  
  17. Install the fuel line brackets and fuel rail.
  18.  
  19. Install the heater hose.
  20.  
  21. Install the upper radiator hose.
  22.  
  23. Install the A/C lines to the compressor.
  24.  
  25. Install the distributor. Note the relationship of the distributor housing and rotor made at disassembly.
  26.  
  27. Install the upper intake manifold using the procedure in this section.
  28.  
  29. Fill the cooling system.
  30.  

The 1996-97 models should have come with DEX-COOL&trade. This orange-color coolant is low in silicates and is designed to protect the aluminum components in the cooling system.

  1. Connect the negative battery cable.
  2.  
  3. Start the engine. Check for coolant, oil and vacuum leaks and for proper engine operation.
  4.  
  5. Install the engine cover.
  6.  
  7. Have the A/C system recharged.
  8.  

 
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