Replacing a heater core is a major undertaking, not a simple bolt-on replacement. It typically involves these steps:
1. Preparation: Disconnect the battery negative terminal. Gather all necessary tools, including screwdrivers (Phillips and flathead), sockets, wrenches, pliers, a drain pan, coolant, and possibly a shop manual specific to your 1996 Impala. A service manual is highly recommended; it will show you exactly what needs to be removed and in what order.
2. Dashboard Disassembly: This is the most time-consuming part. You'll likely need to remove:
* Glove box: This gives initial access to the area.
* Radio and other trim pieces: These need to be carefully removed to expose more of the dashboard.
* Steering column shroud (possibly): Depending on the exact design, some of the steering column components may need to be moved.
* Instrument panel (at least partially): This often requires unbolting and carefully disconnecting electrical connectors. You may need to support the instrument panel while working.
* Various HVAC components: Parts of the air conditioning and heating system will need to be removed or moved to access the heater core.
3. Heater Core Removal: Once the dashboard is sufficiently disassembled, you'll be able to access the heater core. You'll need to disconnect the coolant hoses carefully, likely using pliers and/or wrenches. Have a drain pan ready to catch the coolant. The core itself is typically held in place by retaining clips or bolts.
4. Heater Core Installation: Install the new heater core, ensuring it's properly seated and secure. Reconnect the coolant hoses tightly.
5. Dashboard Reassembly: Carefully reassemble the dashboard, making sure all electrical connectors are properly reconnected.
6. Coolant Refill and Bleed: After reassembly, refill the cooling system with the correct type and amount of coolant, and then bleed the air from the system. This is crucial to prevent overheating.
Disclaimer: This is a general overview. The exact procedures will vary depending on your specific vehicle's configuration. Attempting this repair without the proper tools, experience, and a service manual is strongly discouraged. Incorrectly performed, it could lead to further damage to your vehicle. Consider taking your vehicle to a qualified mechanic for this repair. The cost of labor will likely be substantial given the complexity of the job, but it's far less than the potential costs of doing it incorrectly.
