Heater Core: Service and Repair

LESS A/C
Exc. 1983---88 Century & Cutlass Ciera & 1984---88 Cutlass Cruiser. For service procedures on 1983---88 Century and Cutlass Ciera, refer to models with A/C.
1. Drain cooling system.
2. Remove heater inlet and outlet hoses.
3. Remove radio noise suppression strap.
4. Remove cover retaining screws and cover.
5. Remove heater core.
6. Reverse procedure to install.

WITH A/C
1. Drain cooling system.
2. On all except diesel engine models, disconnect heater inlet and outlet hoses. On diesel engine models, raise vehicle and disconnect heater inlet and outlet hoses, then lower vehicle.
3. On diesel engine models, remove instrument panel lower sound absorber. On all models, working inside vehicle, remove the heater ducts, then the heater case side cover.
4. Remove heater lower outlet.
5. Remove 2 housing cover to air valve housing clips, then the housing cover.
6. Remove heater core retaining straps, core tubing retainers, then the core.
7. Reverse procedure to install.