Symptoms of a Bad or Failing Thermostat

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Cost of Replacing a Bad or Failing Thermostat

Common signs include the temperature gauge reading being very high or changing erratically, engine overheating, and coolant leaks. Our certified technicians can come to you and diagnose the problem. You will receive a $30 credit towards any follow-up repairs that result from the diagnostic. Following are example prices for Car Thermostat Replacement. Click on the button below to get an upfront quote for your car.

Cars Estimate Parts Cost Labor Cost Savings Average Dealer Price
2004 Chevrolet Malibu $198 $57.55 $140.00 27% $272.55
2004 Chevrolet Venture $193 $38.84 $154.00 29% $275.34
2004 Oldsmobile Alero $165 $38.84 $126.00 29% $232.34
2012 BMW 535i xDrive $327 $194.23 $133.00 17% $398.48
2013 Audi A6 $239 $140.81 $98.00 18% $291.31
2009 Chevrolet Corvette $141 $70.97 $70.00 21% $178.47
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How to Diagnose a Bad or Failing Thermostat?

thermostat

A car thermostat regulates the flow of coolant through the engine and is an incredibly important player in the operation of your vehicle’s engine. You may hear the phrase “the thermostat was stuck open or closed.” When the engine has been sitting for a while and is not warm, the thermostat will be closed. Once the engine is running and reaches a certain operating temperature, a sensor inside the thermostat will cause it to open, allowing coolant to flow to and from the radiator, decreasing the temperature so it can be recirculated through the engine again. This constant flow (in conjunction with several other cooling system components) is what keeps your vehicle’s engine functioning at the optimum temperature.

The opening and closing of the thermostat at the correct time is critical to maintaining proper engine temperature. In the event that it happens to become “stuck” closed, there is no way for coolant to be circulated through the radiator and eventually back through the engine, which causes extremely hot engine temperatures. Likewise, if the opposite problem arises in that the thermostat is “stuck” open, the flow of coolant is constant resulting in the vehicle’s engine temperature never reaching an optimum level of heat which creates performance problems. There are several common symptoms associated with a bad or failing thermostat that will alert you that service is due.

1. Temperature gauge reading very high and engine overheating

The first and potentially most alarming symptom will be the temperature gauge reading high into the red within the first 15 minutes of your vehicle engine running. This is often the very first sign that the thermostat is not functioning properly.

2. Temperature changing erratically

Erratic temperature fluctuations can also occur causing dramatic spikes and drops in temperature which eventually leads to poor engine performance. In this case you may see the temperature abnormally low at one point and shortly after climb to an abnormally high level.

3. Coolant leaks around the thermostat housing or under the vehicle

Another indication may also be leaking coolant which can be caused by the thermostat not allowing coolant to flow when it is stuck in the closed position. This can be noticeable in a variety of locations, but most commonly around the thermostat housing. This can eventually cause other coolant hoses to leak as well resulting in coolant often times leaking on the ground under your vehicle.

Thermostat replacement is a fairly inexpensive repair to make to your vehicle, preventing potentially thousands of dollars in engine damage due to excessive heat. If any of the above symptoms sound familiar to you, it may be time to have an expert mechanic from YourMechanic come to your home or office to diagnose your vehicle.

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Recent Car Thermostat Replacement reviews

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YourMechanic Car Thermostat Replacement Service

Average Rating

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Number of Reviews

1,222

Rating Summary
1,144
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5
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1,144
43
9
5
21

Robert

30 years of experience
59 reviews
Robert
30 years of experience
Robert dose excellent work. He was on time, very knowledgeable and professional. I would recommend him to anyone. I will use this service in the future.
2012 JEEP GRAND CHEROKEE - CAR THERMOSTAT REPLACEMENT - DOUGLASVILLE, GEORGIA

Ira

33 years of experience
216 reviews
Ira
33 years of experience
Omg, the best mechanic ever. On time fast but acutely. He did an amazing job. It also rained and he finished his job. I would only request him.
2012 DODGE CHALLENGER - THERMOSTAT - TAMPA, FLORIDA

Eduardo

16 years of experience
160 reviews
Eduardo
16 years of experience
I am completely blown away by the great superior quality of Eduardo’s professionalism, self-sufficiency, and speed of services. It is impressive and a rare occurrence to be so satisfied with performance of services. Rest easy when booking Eduardo because he is a man that will get the job done beyond expectations. Provided clear concise communication on his work and assessed and reported a health check. We will book him to follow up on the vehicle when next maintenance is needed and all other vehicles we own when next needed. Sleep easy knowing you’re booking the best of the best with Eduardo.
2005 MINI COOPER - CAR THERMOSTAT REPLACEMENT - HOUSTON, TEXAS

Sam

14 years of experience
105 reviews
Sam
14 years of experience
Knowledgeable, respectful, and courteous. On time. Definitely utilize his services again. A job well done!
2007 NISSAN MURANO - CAR THERMOSTAT REPLACEMENT - CLOVIS, CALIFORNIA

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