No Heat
existenz618
11-12-2007, 09:47 PM
i recently bought a 1998 honda accord...i bought this car in the summer so being the idoit i am i didnt check the heat. Now its winter and im royaly screwed. i brought my car to my mechanic and he said i need to replace the primary heating coil. The cost is wayyy out of my price range right now but i need heat to defrost my windows. is there any alternative way to heat/defrost my windows...ive tried a small space heater but a cigarette lighter doesnt put out enouph power to use it. Please help
jeffcoslacker
11-13-2007, 07:58 AM
Heater core...that's your only source of heat...gotta have it.
Is it bypassed? Clogged? Leaks?
You won't get any heat if the cooling system is low...check this FIRST...check at the radiator, not the resevoir...
Assuming the engine runs a normal temp, and the cooling system is full, locate the hoses going to and from the heater core (from the engine to the firewall)...when the motor is fully warmed up, both hoses should be equally hot.
There is a heater control valve in one side that must open for the core to get heat. Make sure it is working (have someone run the control from heat to cool with the engine running and watch for movement)...if the control operates but you still have hoses with unequal temp, the core is probably blocked. Once in a while the mechanism works but the actual plate that controls flow has broken loose inside, and is stuck closed. You have to remove the valve and manually operate it to see this happening...
If the heater control valve doesn't do anything, it may be bad, or there may be a problem with the dash control or vacuum circuit...see if there is vacuum at the line that changes when the control is moved from hot to cold (engine running).
Sometimes I've been able to blow a clogged core open by just blowing into the core in the opposite direction of flow or running hose water through it backwards...if one side was cold when testing, that's the side you want to push through...sometimes they'll puke out a big wad of crud and flow normally after...
Did the mechanic actually check it out, or did he just say that was the most likely thing?
Is it bypassed? Clogged? Leaks?
You won't get any heat if the cooling system is low...check this FIRST...check at the radiator, not the resevoir...
Assuming the engine runs a normal temp, and the cooling system is full, locate the hoses going to and from the heater core (from the engine to the firewall)...when the motor is fully warmed up, both hoses should be equally hot.
There is a heater control valve in one side that must open for the core to get heat. Make sure it is working (have someone run the control from heat to cool with the engine running and watch for movement)...if the control operates but you still have hoses with unequal temp, the core is probably blocked. Once in a while the mechanism works but the actual plate that controls flow has broken loose inside, and is stuck closed. You have to remove the valve and manually operate it to see this happening...
If the heater control valve doesn't do anything, it may be bad, or there may be a problem with the dash control or vacuum circuit...see if there is vacuum at the line that changes when the control is moved from hot to cold (engine running).
Sometimes I've been able to blow a clogged core open by just blowing into the core in the opposite direction of flow or running hose water through it backwards...if one side was cold when testing, that's the side you want to push through...sometimes they'll puke out a big wad of crud and flow normally after...
Did the mechanic actually check it out, or did he just say that was the most likely thing?
existenz618
11-13-2007, 02:43 PM
i brought my car to my mech and left it there all day. 45 bucks later he said the primary heating coil needs to be replaced and that im leaking anti freeze because of my head gasket. im gonna check some of this stuff out today myself and see if he could have been wrong....im pretty sure hes right though because he flushed out my car twice and it didnt help.
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