Rep Power: 0

hello : was searching for my problem , but unable to find it .

i have a 2004 honda civic and when ever i come to a stop at a long light my heater blows cold air , heat works perfect while i am on any and all freeways , then get off on the off ramps and sit for a light and there goes the heat ...

this has been happening for a couple years now and last year a freind of my took a good sprayer and attemped to back flush my heater core , which seemed to work for a couple of weeks , but then i was back to the same problem ...

now it seems if i can't keep the car at least 2000 rpms or more i am blowing cold air ...

when car is cold and i start the car it warms up in about 10 min.. and heat is good until i i start driving it then blows cold air until i can drive and keep the rpms up or get on the freeway

car does not over heat or leak any antifreze ...

would like any and all feedback on this

please help me someone

 
Rep Power: 0

It sounds like the heater valve cable has slipped off..

 
Rep Power: 518

Or a head gasket leaking, forcing an air bubble into the heater circuit.

 
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...x2

 
Rep Power: 186

...x3

 
Rep Power: 210

x4

refer to this thread.....

https://www.civicforums.com/forums/1...t-working.html

same problem we just discussed this week

 
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x5

Also could just be air in the system. Try bleeding it, if the air keeps coming back its a blown head gasket.

 
Rep Power: 235

Mine was doing the same thing and it was a clogged heater core.