Little to no heat in cabin - 2012 Civic LX
11-08-2016
#1
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Little to no heat in cabin - 2012 Civic LX
I've had this car for three years with no issues, and the first one that pops up has completely stumped me, so I'm reaching out for advice/help.
This is almost definitely just a coincidence, but I'm throwing this out there anyway....... I've driven this car daily for the three years that I've had it an average of an hour a day due to my commute to/from work. I recently took a two week vacation, so the car sat, and the first time I drove it after coming home was the first day of my heat issue, but it's also the first day that I used the heat due to fall getting here, so as I said, it's probably just a coincidence.
The car has no temp gauge, just a light, so I can't check the temp, but this is the troubleshooting that I've done so far:
1) Confirmed that the coolant level was good.
2) Confirmed that the thermostat is good using a pan of hot water.
3) Confirmed that the heater core is not plugged/blocked by pulling the hoses off at the firewall and putting a garden hose to it in both directions, and it's totally free with no blockage.
4) After the car gets to temp, the "out" and "in" hose from the block to the radiator are both flowing hot.
5) The hoses to the heater core are both the same temp by grabbing them with my hand, although they aren't as hot as the radiator hoses.
6) When I turn the heat selector back and forth between hot and cold, I can see the white gears moving on the side of the center console next to the gas pedal.
7) Lastly, and probably most importantly, I get a little heat on the floor on the passengers side, but ice cold air on the drivers floor side (right on my feet).
Any clues or advice?!?!
Shawn
This is almost definitely just a coincidence, but I'm throwing this out there anyway....... I've driven this car daily for the three years that I've had it an average of an hour a day due to my commute to/from work. I recently took a two week vacation, so the car sat, and the first time I drove it after coming home was the first day of my heat issue, but it's also the first day that I used the heat due to fall getting here, so as I said, it's probably just a coincidence.
The car has no temp gauge, just a light, so I can't check the temp, but this is the troubleshooting that I've done so far:
1) Confirmed that the coolant level was good.
2) Confirmed that the thermostat is good using a pan of hot water.
3) Confirmed that the heater core is not plugged/blocked by pulling the hoses off at the firewall and putting a garden hose to it in both directions, and it's totally free with no blockage.
4) After the car gets to temp, the "out" and "in" hose from the block to the radiator are both flowing hot.
5) The hoses to the heater core are both the same temp by grabbing them with my hand, although they aren't as hot as the radiator hoses.
6) When I turn the heat selector back and forth between hot and cold, I can see the white gears moving on the side of the center console next to the gas pedal.
7) Lastly, and probably most importantly, I get a little heat on the floor on the passengers side, but ice cold air on the drivers floor side (right on my feet).
Any clues or advice?!?!
Shawn
11-08-2016
#2
If you think a good mechanic is expensive, try hiring a bad one
Re: Little to no heat in cabin - 2012 Civic LX
3 thoughts come to mind:
One, possible restriction or garbage buildup inside the heater core (CLR, power flush core by itself, rinse)
Two, undiluted straight antifreeze does not transfer heat well, should be 50/50 mix unless you are in an extreme cold area
Three, air mix door movement problem inside the HVAC housing (even though you can see parts moving on the outside, is everything still working on the inside?)
Without being able to check things firsthand, I might try flushing the core out first.
One, possible restriction or garbage buildup inside the heater core (CLR, power flush core by itself, rinse)
Two, undiluted straight antifreeze does not transfer heat well, should be 50/50 mix unless you are in an extreme cold area
Three, air mix door movement problem inside the HVAC housing (even though you can see parts moving on the outside, is everything still working on the inside?)
Without being able to check things firsthand, I might try flushing the core out first.
11-08-2016
#3
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3 thoughts come to mind:
One, possible restriction or garbage buildup inside the heater core (CLR, power flush core by itself, rinse)
Two, undiluted straight antifreeze does not transfer heat well, should be 50/50 mix unless you are in an extreme cold area
Three, air mix door movement problem inside the HVAC housing (even though you can see parts moving on the outside, is everything still working on the inside?)
Without being able to check things firsthand, I might try flushing the core out first.
One, possible restriction or garbage buildup inside the heater core (CLR, power flush core by itself, rinse)
Two, undiluted straight antifreeze does not transfer heat well, should be 50/50 mix unless you are in an extreme cold area
Three, air mix door movement problem inside the HVAC housing (even though you can see parts moving on the outside, is everything still working on the inside?)
Without being able to check things firsthand, I might try flushing the core out first.
Thank you, but I don't think you read a lot of my post. Its definitely not a plugged heater core since that was part of my troubleshooting. It also wouldn't be the coolant concentration since I mentioned that I have some heat on the passengers side floor but ice cold on the drivers side floor. If it was coolant or heater core, it would be consistent, be it hot, warm or cold.
I'll have to look at the air mix door. I've tried buying a book on the car, but they don't make it yet, so I'll have to figure out how to take it apart and how its supposed to look.
Thanks
Shawn
11-08-2016
#4
If you think a good mechanic is expensive, try hiring a bad one
Re: Little to no heat in cabin - 2012 Civic LX
Yes I did read your post, and a couple things you said caught my attention:
You said the heater hoses were not as hot as the radiator hoses, AND one side was warmer than the other side.
That is why I mentioned the core flush even though you said you had done such already.
Check CRV forums for 2012-14 with poor heater output.....There was a whole bunch that had some sort of trash that ended up trapped in the core, and caused a partial blockage inside the core.
(some people have said it was leftover casting sand, others have said it's residue from the long life coolants)
It also caused a noticeable temperature difference between drivers and passengers sides.
Honda has a service bulletin outlining a pretty intense flushing procedure for the issue on those CRVs. Even though the bulletin only listed CRV specifically, other cars have needed the procedure.
There is also a bulletin for a buzz/rattle/flutter noise in the 12 Civic that comes from a warped air mix door inside the HVAC case.
You said the heater hoses were not as hot as the radiator hoses, AND one side was warmer than the other side.
That is why I mentioned the core flush even though you said you had done such already.
Check CRV forums for 2012-14 with poor heater output.....There was a whole bunch that had some sort of trash that ended up trapped in the core, and caused a partial blockage inside the core.
(some people have said it was leftover casting sand, others have said it's residue from the long life coolants)
It also caused a noticeable temperature difference between drivers and passengers sides.
Honda has a service bulletin outlining a pretty intense flushing procedure for the issue on those CRVs. Even though the bulletin only listed CRV specifically, other cars have needed the procedure.
There is also a bulletin for a buzz/rattle/flutter noise in the 12 Civic that comes from a warped air mix door inside the HVAC case.
11-21-2016
#5
If you think a good mechanic is expensive, try hiring a bad one
Re: Little to no heat in cabin - 2012 Civic LX
From another heat problem thread someone dragged out today:
A HECAT pulsator flush gun may be more effective than a simple garden hose flush.
A HECAT pulsator flush gun may be more effective than a simple garden hose flush.
