How to Clean Clogged Heater Core Fins
- 1). Move the vehicle to a garage or other enclosed area. Pull the hood release lever from inside the vehicle. Open the hood.
- 2). Trace the hoses that run from the water pump to the firewall. This is where they connect to the heater core.
- 3). Remove the hoses from the connection points by releasing the clamps. This can be done with a pair of pliers or by loosing the hose clamps with a screwdriver. Pull the hoses off the connection points.
- 4). Place the end of the garden hose into one of the connection points. Turn on the garden hose so that the water pressure is low. This will force water into the heater core. Any blockage on the heater core fins should be washed away.
- 5). Continue running the water until it runs clear from the other connection point.
- 6). Turn off the water and remove the garden hose. Set the hoses back on the connection points and reset the clamps.
- 7). Start the vehicle and turn on the heat to verify that the heater is working.
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