Cooling system issue

[Transamtony02]

I have had more issues with the cooling system on my 2016 sonic rs than any other car. I have replaced the water pump twice, the thermostat once, and the water outlet 3 times. All new hoses also. Now when I'm driving on the highway for about 30-45 minutes the engine temp light will come on so I pull over shut it off and let it cool. When I look under the hood I can see that the two hoses under the coolant reservoir are wet but they is no active leak. When I start the car back up I can drive another hour with no issues and everything appears dry when I check after reaching my destination. I have also noticed that under normal driving or if I turn the heat on all the way up the cooking fan does not come on but if i turn the a/c on the cooking fan does come on. Does anyone have any insight on what the issue could be? When the a/c is on the two relays next to the coolant reservoir will click on and off turning the fan on and off but not when the a/c is off or heat is on. And the mysterious high temp light during the first leg of my morning commute with wetness on the hoses but no visual leak then no issues the rest of the ride in.

 

[StickyToes]

I've gone through a couple of radiators, a coolant reservoir, and a hose on my 2017 Premier. I still smell coolant every time I shut the car off, but can't find a current leak. I figure it's just the Achilles heel of the car.
My prior 2014 Turbo RS had the water pump replaced, and various cooling system issues, too.

 

[TurtleOverlord]

Cooling problems are common, but that sounds excessive. The over temp light should not come on if there is still coolant in the system, even if there is a leak.

Feel on the bottom of the coolant reservoir for wetness, common leak point.

As for the fan, It is supposed to come on with the AC but not with heat.
By heating the cabin you are taking heat out of the coolant, so no reason to try too cool it more.
AC cools the cabin and dumps the heat to the condenser (right next to the radiator) so it will need cooling and turns the fan on.

 

[shorebreeze]

Have you fully checked the radiator cooling fan? It's a complicated thing compared to, say, a Civic, in that while Honda tend to go with a cooling fan assembly that has two single-speed fans which can be on or off in any combination, Chevy have a three-speed single fan where either damage to the motor or relays can take out some but not all speed settings (Bear in mind that this normally only needs to run at the low or medium settings). This was the end outcome of what added up to the most significant problem I've had with my 2014, namely the radiator overflow bottle cracking and developing a slow leak that it took a long time for me or anyone else to notice. The leaking fluid I suspect corroded the fan motor and the first sign of trouble was when, in warm weather and under load, it clearly had only two speeds -- off, and turboprop-at-takeoff-power (high), a level it normally never attains unless you drive recklessly in hot weather. I had the fan replaced by a third party mechanic but they still didn't notice the cracked bottle; that I saw shortly after, and suddenly all the little hints of coolant smells and occasional odd signs of moisture I'd seen under the hood for quite some time made sense. Combined total cost for replacing the bottle and the radiator cooling fan in two separate visits, the indie mechanic for the cooling fan, the dealer for the bottle, wound up at about $450.

One other incident I had came up as I was driving home from the bottle replacement. Somehow they seem to have got an air lock in the system, at least that was what they concluded after testing it. In any case the turbo shut down and this nasty burning smell came up, though no smoke -- and also apparently no codes. I immediately stopped the car and had the dealer send a tow, for which they did not charge; I took public transport home and awaited the diagnosis and then went back the following day to pick 'er up.

 

[Supersonicturbobaby]

Same here with 2012 1.4 lt . Water punp went out twice , thermostat housing , water outlet like 3 times , coolant surge tank if yellow will start to crack on bottom which i just changed . Radiator hose , t valve by intake and just had a pinhole in radiator which i did today . 112,000 miles

 

[Laakea99]

I have a 2018 sonic turbo and as soon as we bought it we have been dealing with overheating issues. We have replaced the radiator, hoses, thermostat and water pump. In 4 different occasions! It overheats on long drives. We have taken it to chevy for all of these problems and the car is still covered on powertrain. Overheated again the other day! I am done with this car. At this point we should all write to chevy, thos is terrible!

 

[권혁진]

Waterless coolant Evans is recommended.
I'm Waterless Coolant Evans with no thermal expansion pressure
I used and solved it
에반스워터리스쿨런트

 

[BigLee]

Most of the cooling system problems stop happening if you do the "Big 3" cooling system mods.
Cooler Dorman thermostat p/n 902-2080
Lower pressure surge tank cap
Available in 9 or 15 psi.
And last, a radiator mounted auxiliary thermostatic cooling fan switch, that will trigger the low speed fan operation at considerably lower temperature.
Practically all of the cooling system issues these engines encounter seem to vanish after these three mods are done.
Taking the excessive heat and pressure away seems to make all these parts last much longer.

 

[Savage4life2k15]

Most of the cooling system problems stop happening if you do the "Big 3" cooling system mods.
Cooler Dorman thermostat p/n 902-2080
Lower pressure surge tank cap
Available in 9 or 15 psi.
And last, a radiator mounted auxiliary thermostatic cooling fan switch, that will trigger the low speed fan operation at considerably lower temperature.
Practically all of the cooling system issues these engines encounter seem to vanish after these three mods are done.
Taking the excessive heat and pressure away seems to make all these parts last much longer.

How do I know if the thermostat 902-2080 will fit my car

 

[Savage4life2k15]

Most of the cooling system problems stop happening if you do the "Big 3" cooling system mods.
Cooler Dorman thermostat p/n 902-2080
Lower pressure surge tank cap
Available in 9 or 15 psi.
And last, a radiator mounted auxiliary thermostatic cooling fan switch, that will trigger the low speed fan operation at considerably lower temperature.
Practically all of the cooling system issues these engines encounter seem to vanish after these three mods are done.
Taking the excessive heat and pressure away seems to make all these parts last much longer.

How do I know if the thermostat 902-2080 will fit my car

 

[efaily]

I think the wrong part number was linked. Dorman 902-808 appears to be the correct part # for the Sonic. It also doesn't appear that the Dorman part uses a different temperature setting for their thermostat.
https://www.dormanproducts.com/p-83...%20Thermostat%20Housing%20Assembly&origin=YMM

 

[BigLee]

How do I know if the thermostat 902-2080 will fit my car

It will fit 1.4L engines only.
Does not fit the 1.8.
You have to remove the thermostat valve itself from the housing it comes with, as it doesn't have the heater hose fitting on it.
The valve fits directly into the original housing.
Only takes a few minutes to swap.

 

[BigLee]

I think the wrong part number was linked. Dorman 902-808 appears to be the correct part # for the Sonic. It also doesn't appear that the Dorman part uses a different temperature setting for their thermostat.
https://www.dormanproducts.com/p-83493-902-808.aspx?year=2014&make=Chevrolet&model=Sonic&parttype=Coolant%20Thermostat%20Housing%20Assembly&origin=YMM

902-808 is the stock replacement, stock temperature thermostat for the 1.4 turbo.
902-2080 is the stock replacement for the 1.4 N/A engine, in the Volt/ELR models.
902-808 opens at ~217°F.
902-2080 opens at ~176°F.
The N/A thermostat "guts" have to be swapped into the turbo thermostat housing because the N/A housing doesn't have the heater hose fitting on it.

 

[efaily]

Very nice catch! It sounds like you've done this yourself already? How much difference did you notice with the thermostat change? I haven't had any cooling issues with either of my kids Sonics so far, but 221 degrees seems really hot. I've never heard of a another engine using a thermostat that hot. I'm replacing the coolant outlet with a metal one on both cars just to be safe. I might have to try this also.

 

[Hazbro]

Big Lee. can you go into more detail about the "Big 3" cooling system mods? I'm sick of the overheating issues in my 1.4 turbo. I understand the colder thermostat swap and the lower pressure cap. How do I effect the supposed 3 speed fan system so it comes on earlier and/or more reliably?

 

[2019car]

I have had more issues with the cooling system on my 2016 sonic rs than any other car. I have replaced the water pump twice, the thermostat once, and the water outlet 3 times. All new hoses also. Now when I'm driving on the highway for about 30-45 minutes the engine temp light will come on so I pull over shut it off and let it cool. When I look under the hood I can see that the two hoses under the coolant reservoir are wet but they is no active leak. When I start the car back up I can drive another hour with no issues and everything appears dry when I check after reaching my destination. I have also noticed that under normal driving or if I turn the heat on all the way up the cooking fan does not come on but if i turn the a/c on the cooking fan does come on. Does anyone have any insight on what the issue could be? When the a/c is on the two relays next to the coolant reservoir will click on and off turning the fan on and off but not when the a/c is off or heat is on. And the mysterious high temp light during the first leg of my morning commute with wetness on the hoses but no visual leak then no issues the rest of the ride in.

Same issue here. I have had my car since 2019. Loaded in May at 11 miles on it. It has been in the shop in 2020-2022-2023 and October and I just took it back to the shop today in 2024 for their being. No coolant in the coolant reservoir and no heat and the temperature like on...

 

[Thrasher2019RS]

Most of the cooling system problems stop happening if you do the "Big 3" cooling system mods.
Cooler Dorman thermostat p/n 902-2080
Lower pressure surge tank cap
Available in 9 or 15 psi.
And last, a radiator mounted auxiliary thermostatic cooling fan switch, that will trigger the low speed fan operation at considerably lower temperature.
Practically all of the cooling system issues these engines encounter seem to vanish after these three mods are done.
Taking the excessive heat and pressure away seems to make all these parts last much longer.

Dumb question I guess but where do we look for the low pressure surge tank caps?

 

[LilRedLtz]

I swapped the thermostat housing with the ZZP aluminum one that supposedly had a 206° thermostat. The temp usually reads around 213° but sometimes jumps up to 224° and once or twice dropped to 178° is this normal?

 

[Kmpet]

My 2020 now has 25k on it. I change the oil every 5k and the coolant is checked at each service. The first service did not require coolant. Second required some added. All services since have required more coolant added as the reservoir was dry. There are no apparent leaks that I can see. I assume the car is not running too hot as I've never had the temp light come on. No problems on long drives or around town driving. It runs as good as new. I have taken the car in to two mechanics now. Neither found anything unusual and suggested this may just be normal usage over 5k miles. One was a local GM dealership. Should I be concerned or just continue to add the coolant at each service? I'll do the big 3 mods if it is warranted.