Edmunds Answers

Voted Best Answer

  • avatar karjunkie 11/04/09 3:37 pm PST

    You probably have a clogged heater core. This is very easy to check. With the engine at normal operating temperature and the heat on, feel the 2 hoses going into and out of the heater core through the firewall on the passenger side of the engine bay. If one of the hoses is cold, your heater core is clogged. In most cases, this can be cured with a simple radiator coolant flush with the heat turned to hot. If not, you will need to flush the heater core. You can flush the heater core by disconnecting the hoses and connecting your water hose to one end with the other hose set to drain. Turn your water on and off repeatedly to pulse the pressure and dislodged the gunk until the water runs clear and then reconnect the 2 hoses. Make sure you disconnect the battery before you do this and towel dry the engine before you restart it.

Answers

  • karjunkie 11/04/09 3:37 pm PST

    You probably have a clogged heater core. This is very easy to check. With the engine at normal operating temperature and the heat on, feel the 2 hoses going into and out of the heater core through the firewall on the passenger side of the engine bay. If one of the hoses is cold, your heater core is clogged. In most cases, this can be cured with a simple radiator coolant flush with the heat turned to hot. If not, you will need to flush the heater core. You can flush the heater core by disconnecting the hoses and connecting your water hose to one end with the other hose set to drain. Turn your water on and off repeatedly to pulse the pressure and dislodged the gunk until the water runs clear and then reconnect the 2 hoses. Make sure you disconnect the battery before you do this and towel dry the engine before you restart it.

  • obyone 11/04/09 7:32 pm PST

    Could also be low coolant. Check the coolant level in both the radiator and the recovery tank.

  • cb78ta 11/09/09 11:51 am PST

    the heater core was cloged, flushed it out and problem solved. thank you karjunkie.

  • karjunkie 11/09/09 12:32 pm PST

    Glad it all worked out! Make sure to flush the cooling system every 2 years with the heat on full hot. That will prevent the problem in the future!

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