How to Replace 1997 Sunfire Heater Core

If your car&039;s heater is not producing hot air, the heater core can be the source of the problem. The 1997 Pontiac Sunfire is one of the many vehicles on which the heater core can only be accessed by removing the instrument panel within the car&039;s interior. Because you are dealing with an older vehicle, you should make sure you can get a replacement heater core that works for the 1997 Sunfire before you begin this task yourself.

Instructions

Removal

1

Disconnect the negative battery cable, then remove the air bag fuse from the fuse box.

2

Raise the car using a floor jack--a commercial jack will work better than the stock jack--and support the car on jack stands. Place a large container under the radiator beneath the drain plug in the front.

3

Open the coolant reservoir cap in the engine compartment, then twist and remove the radiator drain plug from underneath the car. Let the coolant drain into the container and then reconnect the plug.

4

Disconnect the hoses from the core, loosening their clamps with pliers.

5

Remove the defroster grille, the instrument cluster trim plate, the heater/AC controls, the radio and the air ducts from the instrument panel--use a screwdriver or wrench on all fasteners, pry off the trim plates with a trim stick and disconnect all electrical connectors.

6

Unscrew and remove the end caps along the edges of the instrument panel using the screwdriver, then disconnect the electrical connector for the instrument panel lamp, located behind the panel.

7

Unfasten the retaining screws connecting the instrument panel to the tie bar using the screwdriver. Lift the panel off the bar and remove it from the car.

8

Remove the box-shaped diagnostic reserve module along with its bracket, removing its fasteners with a screwdriver or wrench.

9

Unclip and detach the heater core cover. Unfasten the clamps for the heater core and remove the core from the housing.

Installation

10

Insert and position the replacement heater core within the housing and secure it with the mounting clamps. Connect the heater core cover.

11

Reconnect the diagnostic reserve module along with its bracket.

12

Connect the instrument panel back onto the tie bar and secure it using the mounting screws and screwdriver. Connect the lamp electrical connector behind the panel and then screw the end caps in place.

13

Reconnect the air ducts, radio, heater/AC control panel, instrument cluster trim plate and defroster grille to the instrument panel.

14

Reconnect the heater hoses to the core using the hose clamps and pliers, then lower the car off its jack stands.

15

Fill the radiator and cooling system at the radiator fill neck using a fresh 50-50 mix of water and antifreeze. Use the old coolant only if it is completely clean.

16

Connect the fuse for the air bags in the fuse box and then reconnect the battery cable.