Having problems with your 2004 Honda Civic ?
04 civic heater blows cold air at idle
\015 Cold air at idle, blows warm on the highway. Upper rad hose is hot, lower rad hose is cold. I checked the Thermostat (replaced it actually), flushed the rad. Water Pump seems ok because when I take out the thermostat and run the engine, coolant flows through the system and temp stays too cool. thought I might have an air bubble, but after purging the system I still hae the same problem.\015\012\015\012Any thoughts would be helpful.\015\012\015
You should have hot water on all rad. hoses when the motor is running at a norm. temp. the water is not going through the heater core like it should. you have cutoff valve bad low water are a stopped heater.try a hoter thermostat if none of the above are true.
Repair Help & Product Troubleshooting for 2004 Honda Civic
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