There are a lot of routine maintenance items that need to be done on your car. These include things to listen to, things to replace on a regular basis and things to check to make sure they aren’t wearing out. We have a series of articles about the routine maintenance checks you should be doing on your vehicle every week, every month and every six months. If you’re interested, you can start by reading our first article about weekly routine maintenance.
What does a car thermostat do?
When it comes to your car thermostat, it actually falls outside of the routine maintenance category. The thermostat in your vehicle will most likely not wear out or become less effective over time due to normal driving. Your thermostat is a pretty simple piece of equipment with a pretty simple job. Your thermostat is a valve on your vehicle’s cooling system which regulates how much of the coolant gets recirculated straight back into the engine and how much gets sent out through your radiator to be cooled before it recirculates through your engine. By modulating how much coolant gets sent through the radiator, the thermostat can keep the temperature of the coolant in your engine in a very specific range no matter how warm or cold it is outside. This specific temperature range is the range your engine is designed to operate most efficiently in, getting the maximum power without overheating and damaging any parts. This is usually about 1800F to 2000F.
A car thermostat opens and closes through the use of a bimetallic spring, a wax piston or other thermally controlled device. In a bimetallic spring, there are two different types of metal bonded together. These two types of metal expand at a different rate when they are heated, so as the engine coolant warms up the two metals expand, one to a different length than the other. This causes the spring to straighten which pushes the valve open. Similarly in a wax cylinder there is a wax that melts right around the temperature your engine should operate. When the wax melts, it expands pushing on the cylinder which moves and opens the valve.
When should I replace my car thermostat?
Both of these mechanisms are so simple that there is very little to break, change, or go wrong. There are however some situations where you need to replace the thermostat in your vehicle. If your car ever overheats, it could cause damage to your thermostat. Every vehicle has a temperature gauge to help you make sure your vehicle’s engine is operating in the proper temperature range. If the temperature gauge ever gets more than ¾ of the way up its range, or reaches the red line, you have probably done damage to your thermostat. High temperatures can ruin the bonding on the bimetallic spring or change the properties of the wax cylinder so your thermostat won’t open at the specified temperature it is supposed to.
If either of these situations happen to your car it may be worth replacing your thermostat. Replacing a car thermostat includes the draining and refilling of your vehicle’s cooling system so you may also consider performing a cooling system flush while you are replacing the thermostat. Flushing the cooling system of your car can help remove the buildup and deposits that have formed overtime due to normal use of your vehicle. They can also help remove scale and precipitation caused when your vehicle recently over heated. Since you already are draining your vehicle’s cooling system to replace the thermostat, you are only adding 2 extra steps to your project, adding BlueDevil Radiator Flush and driving for a few days, then draining the system again.
BlueDevil Products can be found on Amazon.com or at AutoZone, Advance Auto Parts, O’Reilly Auto Parts, NAPA, and other major auto parts retailers.
54 responses to "Do I need to Change My Car Thermostat?"
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How much does it cost to fix the car thermostat if u already bought the part
Leiatra-
The labor cost on replacing the thermostat varies greatly between different types of vehicles. On some cars it is a very quick job where other vehicles will require additional parts to be removed to access the thermostat.
Thank You!
-BDP
I bought a used car (Toyota Corolla) from the US and i’m in Sierra Leone.I’m advised to remove the thermostat because of our weather condition.Pls,advise.Thanks.
Abioseh-
Thank you for asking about your Toyota Corolla. Having the thermostat removed from your vehicle will create a free-flow in the cooling system. It would give you better circulation and help the vehicle from overheating, which is not a bad idea when residing in warmer climates. Feel free to contact our technical support line at 888-863-0426 with any other questions.
Thank you!
-BDP
I am moving from New Jersey to Texas & have a 2010 VW. Do I need to change to a different thermostat fro a for warmer climate? If so, what is such thermostat called?
Thanks
Armando
Armando-
You should not have to change the thermostat due to the warmer climate.
Thank you!
-BDP
I have a 2012 Sportage of which my thermostat was removed due to not opening properly. My A.C Tech said that it was not needed since I live in the Bahamas were it is constantly warm/hot weather. Should I keep the thermostat out or have a new one placed in?
Aya-
You would be fine to leave the thermostat out of your Kia Sportage, being that you live in a warmer climate. You would really only run into an issue if you needed heat in the car. Feel free to contact our technical support line at 888-863-0426 with any other questions.
Thank you!
-BDP
My car over heated due to radiator leak and an engine code came on. I fixed the coolant leak, cleared the code. The car runs great now and doesn’t overheat. The thermostat seems to be operating fine. Should I replace it anyway?
Michael,
Thanks for your question about your vehicle’s thermostat. If your temperature gauge shows normal operation of your thermostat then you most likely haven’t damaged it. You may consider watching it closely for the next few hundred miles, especially when going up hills or putting a lot of load on the engine as the most common thing a broken thermostat does is not fully open restricting coolant flow which can cause overheating at high loads.
Thanks again for your question!
-BD Auto Pro
I was told that I need to replace my thermostat and gasket if I am driving one way from California to Ohio next week. I have a 2004 Nissan Altima. Do I need to do this to do this now in order to prevent the engine overheating or can it wait til I get to Ohio?
Shoshanah-
Thank you for asking about your Nissan Altima. Based on your description, we’d recommend changing the thermostat before making your trip. A faulty thermostat could cause the engine to overheat during your trip, which could lead to other issues such as a blown head gasket.
Thank you!
-BDP
I am replacing my radiator and both hoses car runs cool never above 1/3 on the dail would suggest to go ahead and put new one in or just leave the current one in thanks
1999 honda accord lx 4 cylinder automatic
John-
Thank you for asking about your Honda Accord. Based on your description, we would recommend replacing the thermostat when you replace your radiator and hoses. It’s better to be safe than sorry. A faulty thermostat could restrict the circulation of water/coolant in the system and cause the vehicle to overheat, leading to an array of problems. Feel free to contact our technical support line at 888-863-0426 with any other questions.
Thank you!
-BDP
I have a 2006 gmc envoy,,, my check engine light comes on and stays sometimes for weeks… have not noticed any overheating or raise in temp… I dont drive alot… I am taking a trip from oregon to cali and was told to replace my thermastat… I have quotes from 179.00 to 400.00 why such a jump….
Deborah-
Thank you for asking about your GMC Envoy. Thermostat replacement for your vehicle can range from $104-$174 on average. Was there any additional work that needed to be done? We recommend shopping around for a reputable mechanic to do the work at a reasonable price.
Thank you!
-BDP
hi, I am confused about this Thermostat. I checked it out on the internet, and some are saying I shouldn’t removed and you are also telling me is good to remove it. I live in Africa, Liberia and trying to get a Nissan primers P11.plz advise me. thx you, Salim C. Jabateh
Salim-
In terms of using the BlueDevil Head Gasket Sealer (32 oz. yellow label), removing the thermostat is a required step in completing the process. It is not necessary to remove the thermostat for normal vehicle use, unless you plan on replacing it.
Hope this helps!
-BDP
Hello, i have a 05 sebring, and currently the check engine light is on.
I checked with my OBD tester and showing cooling thermostat problem.
When i am driving, my car engine temperature won’t go up quickly. sometimes it stays around the middle,
sometimes very low, around quarter area.
Do i need to change my thermostat? my mechanic says i dont need to, but i am just very concerned
since the engine temperature goes stays up and down.
David-
Thank you for asking about your Chrysler Sebring. Based on your description, we recommend changing the thermostat in your vehicle. A faulty thermostat can give you false temperature readings and could also cause further issues down the line. Feel free to contact our technical support line at 888-863-0426 with any other questions.
Thank you!
-BDP
The heat in my car is not working, could this indicate a problem with the thermostats? (I have 2 in my 2011 avenger). Is there any reason thermostats may need to be replaced for this reason or to perform a heater core flush?
Jen,
Thanks for your question about your Avenger. If your ventilation fan is blowing and it’s only blowing cold air, there could be a few things causing the problem. First, it could be that you’ve got a failed thermostat. If that is the case, the temperature gauge in your car would also read abnormally low not allowing your car to heat up. Also, you’re on the right track that your heater core could be in need of a flush. If the core is clogged or blocked it could be causing your heat not to work. Since your car is relatively new, that seems unlikely that it would be that blocked, but it wouldn’t hurt to flush your cooling system.
The other problem could be with your ventilation system. There is a door in the air ducts that moves to direct air over your heater core if you turn the heat on, or around it if you have the temperature control set to cold. If that door is broken or stuck in the “cold” position it would also make your heat blow cold from the vents.
Thanks again for your question!
-BD Auto Pro
I live in Rhode Island and work at home, so I don’t put a lot of miles on my car these days. I had my Thermostat and gasket replaced in my 2009 Hyundai Accent in November of 2015. I just took it in for regular maintenance in Dec 2016 and was told I needed to replace the Thermostat and gasket again. I had it done, but am wondering how often this needs to be done?
Andrea-
Thank you for asking about your Hyundai Accent. You really shouldn’t need to replace the thermostat unless you notice that it is not working properly. Typically, you can change the thermostat when you replace your radiator or heater hoses.
Thank you!
-BDP
My car produces a burnt rubber smell particularly when it is stopped and this is enhanced when the heat is on. My mechanic told me that I need to replace my thermostat, however it shows a perfectly normal temperature gauge- no overheating at all. He said it may be stuck open. Should I trust him? Thanks!
Jessica-
Based on your description, it is difficult to say that a faulty thermostat is the cause of the burnt rubber smell you are getting. It is possible one of your hoses may have come loose and landed on a hot part of the engine. Whether that is the case or not, changing the thermostat would not correct that issue. You may want to bring the vehicle in for a second opinion.
Thank you!
-BDP
I have a 2008 volvo, and have a leak in the radiator hose. Engline light came on saying low coolant, stop engine. They tell me I need to replace thermostat. The car has never over heated. Is this necessary?
Coreen-
Thank you for asking about your Volvo. It is possible that the thermostat is not functioning properly, causing the cooling system to have poor circulation, and not allowing cooling to flow through the system as it should. After replacing the radiator hose, it would be a good idea to replace the thermostat as well.
Thank you!
-BDP
The job of thermostat in a car is to stop the flow of coolant to the radiator until its engine gets warmed up. When the engine becomes cold, there is no flow of coolant through the engine and when it reaches the operating temperature about 95 degrees Celsius, the thermostat is opened up. So, like other parts of the car, thermostats have to be maintained regularly. You should consult with a professional to check whether there is an issue related to the part, otherwise it may let you to face problems in future.
I found out very recently that my radiator was leaking coolant when my car (almost) overheated several times on a drive home. The gauge reached about 3/4, but never hit the red zone. I’ve been monitoring my temperature gauge and my coolant level, topping off when necessary to compensate for the leak and buy myself a few days before repairs can be done. The temperature gauge has remained at normal operating 1/2, even on steep inclines, since I’ve starting topping off the coolant. I’ve been getting quotes from various highly rated mechanics to find the best deal for repairs, since money is tight. One mechanic recommended I get both hoses and the thermostat replaced with the radiator. Is it necessary to replace the thermostat if it appears to still be in good working order? Is it a costly risk to take to not have it replaced?
Max-
It may not be 100% necessary to replace the thermostat in this case, however, it would be recommended. The thermostat is one of the least expensive parts to replace and often can be the cause of overheating issues or the original cause of the leak, so it makes sense replacing it when the radiator is replaced to ensure it doesn’t cause the new radiator to develop a leak.
Thank you!
-BDP
Our cars, one of humans’ greatest inventions, are indeed complex machines. They are made up of different kinds and sizes of parts and components that all work together for your mobility, driving convenience, safety, and more. Being that all these different vehicle parts have each of their own functions and responsibilities, it is only natural to think that some will wear out and get tired faster than the others.
The thermostat inside my sienna 2004 model was removed because of recent overheating. I live in Nigeria. Please I want to know if this is a good decision
Ade-
Thank you for asking about your Toyota Sienna. Unless you are worried about the functionality of your heat, you would be fine to operate the vehicle with the thermostat removed.
Thank you!
-BDP
I have a 2003 Saturn L300 and my check engine light went on due to my coolant thermostat. Should i get it fixed right away or not really worry about it till down the road. I went to Orilley and the guy said to monitor your car tempature. My car does not over heat it stays at a regular tempature
Moses-
Thank you for asking about your Saturn L300. We’d recommend replacing the thermostat, rather than waiting, to prevent any further issues from occurring. Although it does not seem to be an issue at this time, a faulty thermostat could cause the vehicle to overheat and could potentially blow the head gasket. Feel free to contact our technical support line at 888-863-0426 with any other questions.
Thank you!
-BDP
Hello. I live In Nigeria and my mechanic advised I have my thermostat removed because of a leak in my radiator. I would like to confirm the implication of this as a friend advised not to take out the thermostat. I understand taking it out would wear out the engine and increase fuel consumption. Thanks in anticipation.
Joke-
Removing the thermostat would create a constant free flow in the cooling system, and help the vehicle from overheating. If you are experiencing a lack of flow or a restriction of flow, depending on the mileage of the vehicle, you may want to have the cooling system flushed to get rid of any potential jellied antifreeze or other debris stuck in the system.
Hope this helps!
-BDP
Hi, I have some Questions if you can Help me .
1- My car is Hyundai Elantra 2008 2.0, automatic with 109500 Miles . My heater is Working Perfect, cause I do Drain/refill twice every year, Do you think I need any kind of Flush for Heater core, just the heater core to Maintain in good Condition ? If yes, How ?
2– I’m planning to do timing belt, W/P, Tensioner, Idler pulley, A/C belt and Alternator belt replace at 110 K miles, Is it good Idea to Clean that Heater Core ? I will replace all Coolant Hoses as well and Also Replace thermostat ? Heater core Hoses too, will be replace .
3– When replacing the Coolant hoses, Do they need any kind of sealant or just Push then ?
4– The thermostat coming with paper gasket, Do you think I need to put any RTV or Permatex Sealant together with Paper gasket or not need it ? I bough already Permatex Aviation sealant liquid # 80019. Some Mechanic told me add it.
5– The Water pump also coming with Paper gasket, Can I put Permatex on the Water pump to hold the Paper gasket and help it against leak ?
6 — I will replace the Valve cover gasket as well. some say add RTV or Permatex to the Corners of the Camshaft to avoid Oil leak, Do you think is Necessary with Fel-pro Rubber Gasket ?
7– When do you recommend to replace Camshaft seal and Crank seal ?
—- all in my car is Original at 110 K miles, Only the Timing belt was replace by Dealer at 51 K miles. I really Appreciate your Wise Recommendation . Thank you.
Robert-
Thank you for asking about your Hyundai Elantra. Being that your heater seems to be working in good condition, it doesn’t sound like it would be necessary to flush the heater core out specifically. As long as you are keeping up with the routine maintenance and having the coolant flushed at the recommended intervals, there shouldn’t be any issue with keeping the heater core in good working condition moving forward.
The majority of your questions seem to have to do with the factory recommended service by the vehicle manufacturer. Please contact our technical support line at 888-863-0426 so that we can get a little better understanding of the vehicle’s condition and be able to make any appropriate recommendations.
Thank you!
-BDP
The temperature on my thermostat goes up when going up a hill or accelerating, do I need to replace the thermostat? Any ideas?
Nicholai-
Replacing your thermostat would be a good place to start. A defective thermostat may cause overheating by not opening up at the proper temperataure, allowing for the system to flow freely. Feel free to contact our technical support line at 888-863-0426 with any other questions.
Thank you!
-BDP
I have a 2003 Honda Civic Coupe. I have gone on 2 long trips this year. 1 from Visalia, CA to Ripon CA which is about 2.5hrs one way. On my way back on day 2 my temperature gauge reached all the way up. I saw ZERO smoke and my engine and hood were not blazing hot. My 2nd trip was from Visalia, CA to Santa Cruz, CA which is 3.5 hrs one way. After leaving my car parked for 8 days, half way home my temperature gauge reached the all the way up. Again, same results of no smoke or anything getting extremely hot. Thoughts on replacing my thermostat?
Nick-
Thank you for asking about your Honda Civic. Based on your description, checking the thermostat for proper functionality would be a good place to start. You can remove the thermostat and place it in boiling water to see if it is opening at the correct temperature. If not, then a replacement thermostat would be needed. Another component to look into would be the water pump. Depending on how many miles are on the vehicle, and without noticing a loss of water/coolant, the vehicle may have poor circulation in the cooling system, attributed to a faulty water pump. Feel free to contact our technical support line at 888-863-0426 with any other questions.
Thank you!
-BDP
I have a 2004 grand am that’s overheating if I get a thermostat will it help?
Terrianna-
Replacing the thermostat would only help if that is the cause of the overheating. Has the vehicle been diagnosed at all? If not, you may want to bring it to a certified ASE mechanic for a proper diagnosis.
Thank you!
-BDP
I have corolla 2009. The car is overheating while speed increase than 80 KPH. Rediater fluid is of same level not reduced means no leakage. AC working properly and also fan is OK. Possible reasons for overheating.
Khan-
Thank you for asking about your Toyota Corolla. The best place to start would be to check the thermostat to make sure it is opening/closing properly. If the thermostat has become stuck, it could restrict flow and cause the engine to start overheating. Replacing the thermostat in this case should correct the issue. If the thermostat is functioning properly, you an also look into flushing the cooling system to get rid of any jellied antifreeze or other debris that might be clogging/restricting flow.
Thank you!
-BDP
I have a 2011 jeep liberty one the drivers side it was not clearing my windshield like it should I took it to the garage and they put a thermostat in it brought it home next day the jeep is overheating now they are trying to tell me it need a water pump now what should I do
Genevieve-
Please contact our technical support line at 888-863-0426 so that we can get a little better understanding of the vehicle’s conditon and be able to make any appropriate recommendations.
Thank you!
-BDP
Hi from Norway, I have nissan micra 2011. I dont get the heating or it is not hot enough for the winter. I had to flush it three times and now no heat again even there is no air the the system. Do you think i have to change the thermostat?
Thanks for the answar.
Nils-
Thank you for asking about your Nissan Micra. A faulty thermostat could be the reason behind the vehicle not producing heat. If the thermostat isn’t opening up to allow coolant to flow through the heater core, it will not be able to produce heat. Also, if the thermostat is stuck open, the coolant temperature would remain too low to produce good heat. Replacing the thermostat should fix the issue.
Thank you!
-BDP
Hi, from Nigeria. I recently got gifted with Lexus is250 2007 with 97340 miles from United States and i noticed my temperature gauge rises around the middle during a ride so i decided to visit the nearest mechanic station and i was advised to change the thermostat to a relay and as well as the radiator for a double cell as this will calm down the overheating because of our weather condition.. Please what should i do with such idea?
Francis-
Thank you for asking about your Lexus. Based on your description, replacing the thermostat would be the best place to start. Typically, if the needle is registering in the middle of the temperature gauge, it is indicating normal operating temperature. It is also possible that the coolant temp sensor is faulty and not reading the correct temperature.
Hope this helps!
-BDP