1996 Civic Heater Problems?

Question

I own a 1996 Civic with 179,000 miles on it. the heater recently stopped producing heat. not completely, sometimes it will produce lukewarm air, but thats about it. i dont have any coolant on the floorboards, nor do i smell any. i recently had the coolant flushed and the heater worked after that. the heater has never worked all that well in the past but now i cant even defrost my car. any suggestions before i go to a shop and throw hundreds of dollars at them?

In response to a few answers, the thermostat is brand new, about a year old, and the temp gauge works fine.

If the problem is air in the system, how do I bleed it?

Answer 1

Check to make sure the coolant system is full. Check to see if it has a valve on one of the heater hose going through the firewall and see if it is working. If equipped with A/C, fool with the blend doors under the dash and see if they are moving.

Answer 2

You may have air in the lines from the flushing, or the flush may have forced some rust or scale up into the heater core, causing a blockage. Never let anyone "flush" anything on your car. If you want to make sure all the old coolant is out of the system, fill it with water, run it, then drain the water. Don't "flush" or "power flush" it. Don't flush the transmission, either.

If you don't think it is air, or a blockage, you may have a bad thermostat. Is your temp. gage on the dash coming all the way up as it should? If not, your thermostat may be stuck open. Your heater valve may also not be working properly, and not allowing enough water to circulate through the heater core.

No definite answers, but hopefully this will give you somewhere to start. Good luck.

Answer 3

The problem sounds to me like the heater core is once again clogged and that a reverse flush for the core only is in order
you could do this yourself
find where the two hoses to the core enter the firewall
take them loose and with a garden hose run water through
each go from one side to the other as the water clears up
when there is nothing but clear water mission complete.
core is squeaky clean.
da skinny from Kenny

Answer 4

You might try reversing the hoses' on the heater. This will flush the heater core and perhaps solve your problem. After you run the car for a mile or so, put the hoses' back the way the were.
If it does solve your problem, I would then flush the radiator, and replace with new anti-freeze/water.

Answer 5

The heater core is probably clogged pretty good. You can take the hoses off the core in the engine compartment and try to flush it directly instead of doing the whole system.

Answer 6

make sure the thermostat u replace is a oem part. because aftermarket t-stats have a different heat range, If the t-stat is oem i would check the heater line going into the heater core in and out. if going in is hot and out is warm or cold you may have a stuck or clogged water valve. Air in the system in unlikely it would cause an idle surge....

Answer 7

very possibly it may be the heater core itself!! if you have air in system,when engine is cold, remove rad cap,i mean cold prestart start car let run abit you should see fluid circulating,let it go abit, then should start to bubble over,[hotbecarefull] its ok still ,let it run abit longer,then fluid level should drop a fair bit when the thermastat opens,when fluid drops add antifreeze,replace cap let it run abit more to clear system,that should do it!!try heater and see, should be hot!! maybe a bad themastat,even if new you do get bad ones! stat right side up?? they can be tested in your kitchen!!good luck

Answer 8

S'pore is such a Hot country....Y U stil bother abt such problems??? Most Important...dun kana Overheated ...can Liao!!

Answer 9

it sounds like theheater is plugged up and my need to be replaced or cleaned out