GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 1999 🢒 Intrigue 🢒 Engine 🢒 Engine Mechanical - 3.5L 🢒 Exhaust Manifold Removal

Exhaust Manifold Removal Left


    Object Number: 233866 Size: SH

    Important: It is difficult to mount the engine on an engine stand with the exhaust manifold/crossover pipe in place. When the engine is out of the vehicle, properly support the engine on the floor or bench and remove the exhaust manifold before mounting the engine on an engine stand.

  1. Remove the oil level indicator tube bolt.
  2. Remove the oil level indicator and tube by sliding the tube up through the exhaust manifold.
  3. Remove and discard the O-ring from the oil level indicator tube.

    4. Object Number: 277022 Size: SH
  4. Remove the exhaust manifold heat shield bolts.
  5. Remove the exhaust manifold heat shield.

    6. Object Number: 240838 Size: SH
  6. Loosen the exhaust manifold bolts.

    7. Object Number: 234125 Size: SH
  7. Remove the left exhaust manifold to crossover pipe flange bolts.
  8. Remove the left exhaust manifold bolts.

    9. Important: DO NOT reuse the exhaust manifold gasket or flange gasket.

  9. Remove the left exhaust manifold, exhaust manifold gasket and flange gasket.

    10. Object Number: 281929 Size: SH
  10. Remove the left engine coolant heater bolt.
  11. Remove the left engine coolant heater.

Exhaust Manifold Removal Right


    Object Number: 234135 Size: SH

    Important: It is difficult to mount the engine on an engine stand with the exhaust manifold/crossover pipe in place. When the engine is out of the vehicle, properly support the engine on the floor or bench and remove the exhaust manifold before mounting the engine on an engine stand.

    Important: The EGR valve inlet pipe incorporates a crush seal connection at the water crossover. The EGR valve inlet pipe must be replaced if disconnected from the water crossover.

  1. Disconnect the EGR valve inlet pipe from the exhaust crossover pipe (3).
  2. Remove the EGR valve inlet pipe to water crossover bolt (2).
  3. Remove the EGR valve inlet pipe (1) and discard.

    4. Object Number: 235262 Size: SH
  4. Remove the oxygen sensor (1) from the manifold.
  5. Inspect the oxygen sensor for excessive deposits or damage. Replace the oxygen sensor if necessary.

    6. Object Number: 234122 Size: SH
  6. Remove the right exhaust manifold bolts.

    7. Important: DO NOT reuse the exhaust manifold gasket.

  7. Remove the right exhaust manifold and exhaust manifold gasket.

    8. Object Number: 483110 Size: SH
  8. Disconnect the engine wiring harness from the knock sensor.
  9. Remove the engine wiring harness from the wiring harness bracket (1).

    10. Object Number: 483108 Size: SH
  10. Remove the engine wiring harness from the lower crankcase.

    11. Object Number: 483099 Size: SH
  11. Disconnect the engine wiring harness from the ECT sensor.
  12. Remove the engine wiring harness.

    13. Object Number: 235257 Size: SH
  13. Remove the ECT sensor.

    14. Object Number: 483127 Size: SH
  14. Remove the oil pressure switch.

    15. Object Number: 483083 Size: SH
  15. Remove the wiring harness bracket bolt.
  16. Remove the wiring harness bracket.

    17. Object Number: 483079 Size: SH
  17. Remove the knock sensor.

    18. Object Number: 281918 Size: SH
  18. Remove the right engine coolant heater bolt.
  19. Remove the right engine coolant heater.

Exhaust Manifold Removal Left with RPO NB7


    Object Number: 233866 Size: SH

    Important: It is difficult to mount the engine on an engine stand with the exhaust manifold/crossover pipe in place. When the engine is out of the vehicle, properly support the engine on the floor or bench and remove the exhaust manifold before mounting the engine on an engine stand.

  1. Remove the oil level indicator tube bolt.
  2. Remove the oil level indicator and tube by sliding the tube up through the exhaust manifold.
  3. Remove and discard the O-ring from the oil level indicator tube.

    4. Object Number: 483149 Size: SH
  4. Remove the A.I.R. vacuum hose from the retaining clip on the engine lift bracket.

    5. Object Number: 483143 Size: SH
  5. Disconnect the A.I.R. vacuum hose from the throttle body.

    6. Object Number: 234326 Size: SH
  6. Disconnect the vacuum tube (1) from the A.I.R. control valve (2).
  7. Disconnect the feed pipe nut (3) from the exhaust manifold.
  8. Remove the A.I.R. control valve bolt.
  9. Remove the A.I.R. control valve from the torque strut bracket.

    10. Object Number: 277022 Size: SH
  10. Remove the exhaust manifold heat shield bolts.
  11. Remove the exhaust manifold heat shield.

    12. Object Number: 240838 Size: SH
  12. Loosen the exhaust manifold bolts.

    13. Object Number: 234125 Size: SH
  13. Remove the left exhaust manifold to crossover pipe flange bolts.
  14. Remove the left exhaust manifold bolts.

    15. Important: DO NOT reuse the exhaust manifold gasket or flange gasket.

  15. Remove the left exhaust manifold, exhaust manifold gasket and flange gasket.

    16. Object Number: 281929 Size: SH
  16. Remove the left engine coolant heater bolt.
  17. Remove the left engine coolant heater.