Your vehicle’s thermostat is a vital tool that is designed for measuring the temperature of the coolant in the engine. You can usually find the corresponding thermostat gauge, or dial, on the dashboard. This gauge tells you what the thermostat readings are and whether you may have an issue.

Specifically, the dial alerts you about the state of the coolant–whether it is too cool, normal, or if it is overheating. If the gauge shows a too low or high reading then you need to look into whether the thermostat is working properly, or if you have a corresponding issue in the engine. If you ignore a faulty thermostat it could cause further damage to the operation and functionality of your engine.

A high reading on the temperature gauge could mean any number of problems from a coolant leak, a water pump malfunction, or broken thermostat gauge. It could be displaying an inaccurate temperature. In this case, your car may not be overheating, but your temperature gauge won’t be able to warn you.

Thermostats can often go bad after about 10 years of use. If you have either bought an older vehicle or you have not checked yours in a long time, then you need to be able to recognize the signs that the thermostat may not be working. Here are five easily recognizable signs that will alert you that the thermostat needs fixing.

Signs Your Thermostat Is Broken

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1. You Notice Erratic Temperature Changes

Your vehicle’s thermostat may also affect the temperature of the air coming from your air conditioning and heating systems. If you notice sudden and erratic temperature changes from cold to hot or hot to cold, then it could be a sign that your thermostat has stopped working correctly. Get your vehicle inspected if you notice these extreme temperature changes in your vehicle interior.

2. You Find Incorrect Readings on the Temperature Gauge

The temperature gauge will read cold until your vehicle has had time to warm up, after which, it should register the average temperature. If it continues to read too cold or registers too hot, then there is the chance that the temperature gauge should be replaced. If working correctly and your vehicle keeps overheating, then there may be an issue with the coolant or engine itself. If too cold, then the thermostat could be stuck open, causing overcooling. In this case, the thermostat may also need replacing.

3. Your Vehicle Makes Concerning Noises

It is never a good sign when your vehicle makes irregular sounds. If your thermostat is not working properly, you might hear rumbling sounds coming from the engine because the coolant in the radiator is boiling. It could sound like knocking, boiling, or gurgling. Any of these could point to a serious problem in your cooling system because your thermostat isn’t reading the coolant temperature correctly.

4. You Find Coolant Leaks

If the thermostat fails in its closed position, then this can cause the coolant to overflow and leak out of the thermostat container when the engine overheats. If you find coolant leakage, it could be a sign that the thermostat has broken and requires replacement. The easiest way to see whether your vehicle is leaking coolant is to check underneath the vehicle. If you find red-ish or green-ish appearing liquid staining the ground, you probably have a coolant leakage problem.
If you avoid getting this problem fixed, then you will begin to have a leaking problem with the coolant hoses, and this could continue to affect other related parts. If you find coolant leaks under your vehicle, then be sure to visit your local Salt Lake auto repair store.

5. You Notice Problems with the Heating System

If driving during the winter or in a cooler climate, your thermostat may get stuck in an open position which will affect the heating system. If stuck open, the thermostat will allow coolant to continue to flow into the engine, even when it doesn’t require more coolant. If this happens, and you turn the heater on simultaneously, then only cool air will come out of the vents, no matter how high you turn up the heat.
In cases where you don’t require hot air blowing out the vents, you can still check to see if the thermostat is stuck open. Look at the needle on the thermostat gauge and see whether it moves slowly before it stops before the normal point on the gauge. If this is the case, then crank up the heater to see if it blows hot or cold air. If it blows cold air, then most likely the thermostat is broken.

Because so many other engine parts rely on the thermostat’s functionality and readings, you should be sure to get the thermostat looked at or replaced if you think it might be faulty. Otherwise, your engine could suffer irreversible damage and other serious problems.

Contact your mechanic today at Burt Brothers to get the best Utah auto repair services and shop tires at any of our 14 locations from Park City to Sandy.