GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Other than checking for a worn grommet and loose electrical connectors, the only service possible is a unit replacement if the diagnosis shows a malfunctioning MAP sensor.

  1. Turn OFF the ignition.
  2. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim.

  3. Object Number: 421253  Size: SH
  4. Disconnect the MAP sensor harness connector.
  5. Notice: Do not rotate or pry on the MAP sensor when removing. Damage to the MAP sensor or the intake manifold may result.


    Object Number: 421259  Size: SH

    Important: If the original MAP sensor is to be reused after removing the MAP sensor from the intake manifold, replace the MAP sensor to intake manifold grommet.

  6. Remove the MAP sensor by pulling straight up with a slight rocking motion.
  7. Remove and discard the MAP sensor grommet.

Installation Procedure


    Object Number: 421259  Size: SH
  1. Install the new MAP sensor grommet on the MAP sensor.
  2. Install the MAP sensor.

  3. Object Number: 421253  Size: SH
  4. Connect the MAP sensor harness connector.
  5. Reinstall the engine cover. Refer to Engine Cover Replacement in Interior Trim.