SSpeckerwood
New member
Sounds like a heater core.
Coolant Smell only when running heat
- Thread starter Stev3FrencH
- Start date
Stev3FrencH
New member
Well the dealer told me they found no leaks after the pressure check. Everything looked fine. So I guess they are gonna replace the heater core and "hope" that fixes it.
Chevrolet Customer Care
New member
Hi Stev3French,
Will you have a loaner car while they replace your heater core? Hopefully it's not too long you're without your Sonic.
Please private message me if you have additional concerns or questions and continue to post on how things progress. Have a great weekend!
Vanessa
GM Customer Service
just found this message post. i have the same problem with my sonic 1.4t. i have been watching my antifreeze get lower and lower for about 3 months now. also have a sweet smell when the heater is on. another problem i have is after about 2 weeks of driving the car there is a white haze on the lower part of the windshield on the inside. i clean it and it returns in about 2 weeks. on Saturday of last week my coolant reservoir was empty. also when i start it and 1st step on the gas you could hear water rushing into the car. I took the car into the dealer last night and the dealer claims that when the car was brought in the level was "magically" at the correct level.. they say they put a pressure gauge on it and it held pressure.. today when i went in to pick it up the level was higher than i have ever seen it. they claim they put no antifreeze in it. i think the heater core is leaking and they are just waiting for the warranty to be up. the car has 31000 miles on it..
SSpeckerwood
New member
Take it to a different dealer. Obviously they is tryin to **** you.
Stev3FrencH
New member
Well I am sorry to say I never actually was able to get this fixed, it just stopped with time. I've come across a whole new problem though which hasnt been able to be fixed. Once the car warms up I get a loud high pitched whine outta the motor. Almost sounds like the alternator, but ive had it replaced already. They actually pulled the motor and replaced the cylinder head which fixed the problem for 2k miles. Problem is back as of tonight so back in it goes. Good luck getting your smell problem fixed.
american_tuner
New member
Had an old fox mustang that did the same thing and it was a bad heater core. Not saying that's it but it just may be
5.0
Member
just found this message post. i have the same problem with my sonic 1.4t. i have been watching my antifreeze get lower and lower for about 3 months now. also have a sweet smell when the heater is on. another problem i have is after about 2 weeks of driving the car there is a white haze on the lower part of the windshield on the inside. i clean it and it returns in about 2 weeks. on Saturday of last week my coolant reservoir was empty. also when i start it and 1st step on the gas you could hear water rushing into the car. I took the car into the dealer last night and the dealer claims that when the car was brought in the level was "magically" at the correct level.. they say they put a pressure gauge on it and it held pressure.. today when i went in to pick it up the level was higher than i have ever seen it. they claim they put no antifreeze in it. i think the heater core is leaking and they are just waiting for the warranty to be up. the car has 31000 miles on it..
Coolant smell+ oily haze on the window are tell tale signs of the heater core going out. I had to replace one in my old dakota. What a job that was.
ChrisJ
Active member
FYI its not difficult nor does it take long to do a pressure test on a coolant system. It involves a tiny handheld pump that connects in place of the radiator (or in our case coolant tank) cap.
When I can't find a leak I drain the system and then fill it with air pressure from the same pump mentioned above, air leaks faster, and easier than water through a hole.
If a heatercore does not leak any air at 17PSI over a period of an hour I would say there is no way it could ever leak coolant. IF that pressure slowly drops there is obviously a leak and it must be found.
It really is black and white like that. Either it drops and there is a leak, or it doesn't drop and there isn't a leak. Whenever I do a test I usually let it sit and go eat something and relax.
When I can't find a leak I drain the system and then fill it with air pressure from the same pump mentioned above, air leaks faster, and easier than water through a hole.
If a heatercore does not leak any air at 17PSI over a period of an hour I would say there is no way it could ever leak coolant. IF that pressure slowly drops there is obviously a leak and it must be found.
It really is black and white like that. Either it drops and there is a leak, or it doesn't drop and there isn't a leak. Whenever I do a test I usually let it sit and go eat something and relax.
sx sonic
New member
That's is most unfournate that the dealer was not able to fix your problem and worse that they denied any possibility of one. Your problem indeed does sound like a heater core leak to a "T". You could either 1. Go back to that dealer and "persuade" them that there is in fact a problem and make sure they are aware of everything you shared in here ( smell, dirty inside windshield, slow loss of coolant). 2. Go back to dealer next time coolant is low and point out resevoir level and confirm they are aware of your previous issue 3. Try a new dealer and tell them what you told us.
ChirsJ brought up some valid points. I'm assuming the technician put on a pressure tester and left it on for 10-15mins and saw no or negligible drop in pressure, topped off coolant and called it good and on 98% of leaks a psi would be noticed fairly quickly
Since it sounds like you have a slow leak, next time your in for service request that they pressure test it for an hour or so.
Good luck
-tyler
ChirsJ brought up some valid points. I'm assuming the technician put on a pressure tester and left it on for 10-15mins and saw no or negligible drop in pressure, topped off coolant and called it good and on 98% of leaks a psi would be noticed fairly quickly
Since it sounds like you have a slow leak, next time your in for service request that they pressure test it for an hour or so.
Good luck
-tyler
ChrisJ
Active member
This probably isn't a good option for most but this is the type of tester I was talking about. It comes in handy sometimes.
Stant 12270 30 Pound Cooling System And Pressure Cap Tester : Amazon.com : Automotive
You never know, if you need to fight with a dealer to fix something then maybe spending $80 on one to prove your point is worth it. I don't know.
Keep in mind, it apparently is capable of 30PSI but on a system like the Sonic which probably has a 15PSI pressure cap I wouldn't go over 17 or 18PSI.
You may need an adapter to make it fit GMs newer style connector. I think it comes designed for the older twist on caps.
Stant 12270 30 Pound Cooling System And Pressure Cap Tester : Amazon.com : Automotive
You never know, if you need to fight with a dealer to fix something then maybe spending $80 on one to prove your point is worth it. I don't know.
Keep in mind, it apparently is capable of 30PSI but on a system like the Sonic which probably has a 15PSI pressure cap I wouldn't go over 17 or 18PSI.
You may need an adapter to make it fit GMs newer style connector. I think it comes designed for the older twist on caps.
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i was considering getting a pressure tester. I had the service writer confirm the level of the coolant when i left. I told him that i would be back in a couple of weeks when it was lower and then they would have to admit that there was a leak and fix it. I have noticed that since i took it in (and they added coolant) the car gets to temperature a lot faster now. before it was taking about 12-15 miles before the temp. got to 200+. now it is there in 5-10 miles. also i have not heard the water come rushing in to the heater core when i rev. it up like before. i have had a couple of other problems like this with this dealer and have wondered why? why they do this? I have no answer but i am considering finding a new dealer..
thank you to all for the ideas..
thank you to all for the ideas..
ChrisJ
Active member
i was considering getting a pressure tester. I had the service writer confirm the level of the coolant when i left. I told him that i would be back in a couple of weeks when it was lower and then they would have to admit that there was a leak and fix it. I have noticed that since i took it in (and they added coolant) the car gets to temperature a lot faster now. before it was taking about 12-15 miles before the temp. got to 200+. now it is there in 5-10 miles. also i have not heard the water come rushing in to the heater core when i rev. it up like before. i have had a couple of other problems like this with this dealer and have wondered why? why they do this? I have no answer but i am considering finding a new dealer..
thank you to all for the ideas..
Weird, I would suspect hearing water in the heatercore would mean air is in the system and that is BAD with modern coolants. Air is what was mainly responsible for all of the dexcool sludging problems 10 years ago. I suspect this is why our cars have the tiny little hose going to the overflow tank which acts as an automatic bleeder, removing air from the system continuously and automatically.
The thermostats in these cars are computer controlled, so not sure why yours is heating up faster. Problem is I barely know anything about these newer systems so who knows what could be different.
Out of curiosity, since they touched it have you noticed anymore loss of coolant?
Also, one thing I noticed on both my Sonic and Cruze was when I released the pressure from the overflow tank the level came up. Once the car was run again and built pressure the level went back down and stayed down. I assume this is due to stretching of the hoses, but I have no idea really. I just made sure my level in the tank was around or slightly over full when cold after running a few times, this made it slightly overfilled with the cap off. Since then they have not moved. I figured I'd mention it just in case your level dropped, but then stayed where it was rather than a slowly continuous drop.
Just in case, by full I mean the mark on the overflow tank, not literally full. If you ever filled it completely it would get messy.
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Chevrolet Customer Care
New member
Coolant Smell
Hello mcknz323,
I have documented your concern as well as others on this thread regarding the Coolant smell that owners have experienced. Obviously, there's something wrong here.
If you continue to have this issue, I would suggest taking it back into the dealership (or a different dealership) to have them diagnose. I would be glad to set up a Customer Service case, schedule an appointment and contact the dealer to discuss. If so, please private message me your last 8-digits of your VIN, full name, current miles and your contact phone number.
Vanessa
GM Customer Service
just found this message post. i have the same problem with my sonic 1.4t. i have been watching my antifreeze get lower and lower for about 3 months now. also have a sweet smell when the heater is on. another problem i have is after about 2 weeks of driving the car there is a white haze on the lower part of the windshield on the inside. i clean it and it returns in about 2 weeks. on Saturday of last week my coolant reservoir was empty. also when i start it and 1st step on the gas you could hear water rushing into the car. I took the car into the dealer last night and the dealer claims that when the car was brought in the level was "magically" at the correct level.. they say they put a pressure gauge on it and it held pressure.. today when i went in to pick it up the level was higher than i have ever seen it. they claim they put no antifreeze in it. i think the heater core is leaking and they are just waiting for the warranty to be up. the car has 31000 miles on it..
Hello mcknz323,
I have documented your concern as well as others on this thread regarding the Coolant smell that owners have experienced. Obviously, there's something wrong here.
If you continue to have this issue, I would suggest taking it back into the dealership (or a different dealership) to have them diagnose. I would be glad to set up a Customer Service case, schedule an appointment and contact the dealer to discuss. If so, please private message me your last 8-digits of your VIN, full name, current miles and your contact phone number.
Vanessa
GM Customer Service
ChrisJ
Active member
You know what I find odd is this is in the 1.4T section while both 1.8 and 1.4 use the same exact heater core which of course, makes sense.
Fact is if there are a lot of bad heater cores out there both 1.8 and 1.4 would have them.
This thread should really be in the general section IMO.
Fact is if there are a lot of bad heater cores out there both 1.8 and 1.4 would have them.
This thread should really be in the general section IMO.
I just found this thread. The heater on my 2012 Sonic LT is not blowing hot air. My friend's brother checked the coolant overflow and it was empty. He than checked for leaks and did not find any. When he checked the radiator it was down as well so he filled the overflow and I believe the radiator. Mentioned that it may be be the HeatCore which i hear will be costly as I am now no longer on warranty. I called the dearlership and the manager said that I will need to call first thing in the morning to schedule an appt with the service department.
Papasonic
Active member
May I ask how it is no longer in warranty?
If the heater core was leaking enough to empty the coolant reservoir, you would probably notice an odor of coolant from the hvac system, and possibly leakage on the passenger side floor mat area.