Heater blows cold
01-15-2017, 01:48 PM
#1
New Member
Thread Starter
Join Date: 01-15-2017
Location: Santa Cruz, CA
Posts: 28
Heater blows cold
Hey, new here :-)
My heater is blowing cold for most of the time with a period of here or there that it will get hot and may go back to cold and stay cold. Coolant level is full and temp stays normal. Before I start throwing parts at it as a guessing game, has anyone experienced this with their car?
Thanks!
My heater is blowing cold for most of the time with a period of here or there that it will get hot and may go back to cold and stay cold. Coolant level is full and temp stays normal. Before I start throwing parts at it as a guessing game, has anyone experienced this with their car?
Thanks!
01-15-2017, 02:20 PM
#2
Administrator
Join Date: 10-13-2011
Location: Welland,Ont Canada
Posts: 36,509
Welcome to the site, yes, it was the thermostat, if you have not changed it or the coolant, time to do just that!
We highly recommend using Dexcool in a 50/50 mix with distilled water!
And get the correct AC Delco thermostat, other brands don't seem to open in the time frame the computer is looking for, this causes the CEL to come on and the code P0128.
Read this handy how to!
https://www.chevyhhr.net/forums/how-...l-p0128-24493/
http://www.jcwhitney.com/p3042205/sku-3503285.jcwx
We highly recommend using Dexcool in a 50/50 mix with distilled water!
And get the correct AC Delco thermostat, other brands don't seem to open in the time frame the computer is looking for, this causes the CEL to come on and the code P0128.
Read this handy how to!
https://www.chevyhhr.net/forums/how-...l-p0128-24493/
http://www.jcwhitney.com/p3042205/sku-3503285.jcwx
01-15-2017, 03:19 PM
#3
Platinum Member
Join Date: 12-06-2009
Location: Alabama
Posts: 11,098
Welcome to the site. 
It helps us help you if you give the cars info like year, model, mileage, how long you've owned it, etc.
You stated "temp stays normal". If you mean by the gauge on the dash, they're not real accurate. Turn to the digital coolant temp reading in the car's info center and check it there. Below 180 degrees after warm up usually will point to a bad thermostat.
Most likely it's the thermostat as Oldblue said. Start with that 1st. If that's not it you may have a blend door problem under the dash. ( a kind of rare issue)
Blend door is way more complicated to fix.
It helps us help you if you give the cars info like year, model, mileage, how long you've owned it, etc.
You stated "temp stays normal". If you mean by the gauge on the dash, they're not real accurate. Turn to the digital coolant temp reading in the car's info center and check it there. Below 180 degrees after warm up usually will point to a bad thermostat.
Most likely it's the thermostat as Oldblue said. Start with that 1st. If that's not it you may have a blend door problem under the dash. ( a kind of rare issue)
Blend door is way more complicated to fix.
01-15-2017, 03:35 PM
#4
Technical Moderator
Join Date: 01-23-2009
Location: Fredericksburg, Virginia
Posts: 24,692
Did you not have a check engine light?
By coolant temp do you mean the digital read out or the analog.
If no check engine light and the digital temp is around 180F, I think you probably have either an air bubble or a clog in the heater core.
By coolant temp do you mean the digital read out or the analog.
If no check engine light and the digital temp is around 180F, I think you probably have either an air bubble or a clog in the heater core.
01-15-2017, 04:40 PM
#5
New Member
Thread Starter
Join Date: 01-15-2017
Location: Santa Cruz, CA
Posts: 28
The digital temp sits about 180 and ya no check engine light
01-15-2017, 05:33 PM
#6
New Member
Thread Starter
Join Date: 01-15-2017
Location: Santa Cruz, CA
Posts: 28
Welcome to the site.
It helps us help you if you give the cars info like year, model, mileage, how long you've owned it, etc.
You stated "temp stays normal". If you mean by the gauge on the dash, they're not real accurate. Turn to the digital coolant temp reading in the car's info center and check it there. Below 180 degrees after warm up usually will point to a bad thermostat.
Most likely it's the thermostat as Oldblue said. Start with that 1st. If that's not it you may have a blend door problem under the dash. ( a kind of rare issue)
Blend door is way more complicated to fix.
It helps us help you if you give the cars info like year, model, mileage, how long you've owned it, etc.
You stated "temp stays normal". If you mean by the gauge on the dash, they're not real accurate. Turn to the digital coolant temp reading in the car's info center and check it there. Below 180 degrees after warm up usually will point to a bad thermostat.
Most likely it's the thermostat as Oldblue said. Start with that 1st. If that's not it you may have a blend door problem under the dash. ( a kind of rare issue)
Blend door is way more complicated to fix.
It's an 08 SS with 85,000, original owner.......yea I think the thermostat might be a good start. I'll double check again what the digital temp is sitting at.
01-15-2017, 05:59 PM
#7
Platinum Member
Join Date: 12-06-2009
Location: Alabama
Posts: 11,098
180 F would be a little low compared to what other SS owners see. Mine usually stays around 185 to 190 while moving. Can get a little hotter while sitting at a red light.
Many HHR owners have experienced thermostat problems. Both in the regular and SS models.
The original thermostat design wasn't very good for the long term. They can fail because the rubber O-ring deteriorates and dislodges from the center of the stat.
P.S. If you're the original owner and have never changed the Dexcool, you're overdue. Now is a good time for a thermostat and coolant change.
Many HHR owners have experienced thermostat problems. Both in the regular and SS models.
The original thermostat design wasn't very good for the long term. They can fail because the rubber O-ring deteriorates and dislodges from the center of the stat.
P.S. If you're the original owner and have never changed the Dexcool, you're overdue. Now is a good time for a thermostat and coolant change.
01-15-2017, 08:57 PM
#9
New Member
Thread Starter
Join Date: 01-15-2017
Location: Santa Cruz, CA
Posts: 28
180 F would be a little low compared to what other SS owners see. Mine usually stays around 185 to 190 while moving. Can get a little hotter while sitting at a red light.
Many HHR owners have experienced thermostat problems. Both in the regular and SS models.
The original thermostat design wasn't very good for the long term. They can fail because the rubber O-ring deteriorates and dislodges from the center of the stat.
P.S. If you're the original owner and have never changed the Dexcool, you're overdue. Now is a good time for a thermostat and coolant change.
Many HHR owners have experienced thermostat problems. Both in the regular and SS models.
The original thermostat design wasn't very good for the long term. They can fail because the rubber O-ring deteriorates and dislodges from the center of the stat.
P.S. If you're the original owner and have never changed the Dexcool, you're overdue. Now is a good time for a thermostat and coolant change.