GM Service Manual Online
For 1990-2009 cars only

Coolant Heater Replacement VIN C

Removal Procedure


    Object Number: 185620  Size: SH
  1. Remove the master cylinder from the vacuum booster and position out of the way. Refer to Master Cylinder Replacement in Brakes.
  2. Remove the wiring harness and transmission vent tube from the engine lift bracket and position out of the way.
  3. Remove the shift cable from the transaxle.
  4. Remove the Park/neutral safety switch from the transaxle and position out of the way. Refer to Park/Neutral Safety Switch in Automatic Transaxle.
  5. Disconnect the engine block heater connector.

  6. Object Number: 185621  Size: SH
  7. Remove the engine block heater by pulling back on the tab and sliding out of the block.

Installation Procedure


    Object Number: 185621  Size: SH
  1. Install the engine block heater into the block.

  2. Object Number: 185620  Size: SH

    Notice: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.

  3. Connect the heater cord to the engine block heater.
  4. Install the park/neutral safety switch to the transaxle. Refer to Park/Neutral Safety Switch Replacement in Automatic Transaxle.
  5. Install the shift cable to the transaxle.
  6. Install the wiring harness and transmission vent tube to the engine lift bracket.
  7. Install the master cylinder to the vacuum booster. Refer to Master Cylinder Replacement in Brakes.

Coolant Heater Replacement VIN 1

Removal Procedure


    Object Number: 185957  Size: SH
  1. Drain the engine coolant. Refer to Cooling System Draining and Filling .
  2. Remove the transaxle brace to the engine assembly. Refer to Transaxle Brace Replacement in Transaxle.
  3. Remove the cord from the engine coolant heater.

  4. Object Number: 185960  Size: SH
  5. Loosen the bolt at the engine coolant heater but do not remove.
  6. Remove the engine coolant heater.
  7. Remove and clean any burrs, compound, paint, or rough spots from the core plug hole.

Installation Procedure


    Object Number: 185960  Size: SH
  1. Apply a coat of Permatex® Thread Sealant with Teflon to the O-ring and clean the surface of the plug opening.
  2. Install the coolant heater by pushing tight to the block.
  3. Install the coolant heater so the element is positioned as shown.

  4. Object Number: 185959  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  5. Tighten the bolt until both locking wings draw tight against the inner wall of the engine block.
  6. Tighten
    Tighten the bolt to 2 N·m (17 lb in).


    Object Number: 185957  Size: SH

    Notice: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.

  7. Install the heater cord to the engine coolant heater.
  8. Fill the engine cooling system. Refer to Cooling System Draining and Filling .