If it does not open or starts to and stops, this thermostat has failed. Even Even if your car will be sitting for a period of only a few weeks, itâs important that you take steps to store it properly or you will risk having mechanical problems crop up from disuse â some of... Every driver wants a car that lasts a long time. This image is not<\/b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. A car's heater core is like a … A properly and routinely maintained cooling system will have a smaller chance of its thermostat getting stuck closed. i dont have hot air in my car,is there any ways to check it if it is working properly?i don't want to bring the thermostat and boil it to see whether it is working .how do mechanics diagnose it? 2016 Holden Cruze Equip 1.8L & license number is ***** Mechanic's … Another easy way to … For more tips, like how to test your thermostat at home, read on. That's because every pound of pressure the cooling system builds increases the boiling temp of water by 3 degrees. 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. Step 1: Check your gauge. This image is not<\/b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. This image is not<\/b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. Remove the thermostat from the thermostat housing. Take the cap off of your radiator. wikiHow marks an article as reader-approved once it receives enough positive feedback. Prev NEXT . Then, drain the coolant from the lower hose into the bucket. Rather buy a new one and be done with it. Thermostat Not Working? One sign of this is an erratic temperature gauge where the engine goes up and then down in thermal temperature. If you notice your vehicle overheating, turn off the engine right away to avoid causing further damage. In my e46 BMW n42b20 engine, the gauge works normally, but when I drive at a high speed or if the weather is cold, the gauge drops as a result and the heater gets cold. For more tips, like how to test your thermostat at home, read on. 6 Answers. It stays closed when your coolant is cold, letting it get warmed more quickly by the heat of the engine. This image is not<\/b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. Loosen it to release some coolant.If you decide to not remove the coolant note that there will be coolant spilling from the radiator hose and thermostat when you remove the thermostat from the housing. Generally, if your vehicle is overheating within 15 minutes or so of driving it, this may be a sign that the thermostat is stuck. If the upper large black radiator hose is hot after the car has been warmed-up the fault could be the heater-core valve, heater blower motor or the heater shutter doors. Your vehicle’s thermostat opens to allow coolant to flow through the radiator and cool the engine down. Thank You!! This image is not<\/b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. How Long Does a Coolant Recovery Reservoir Last? It's better to spend $4-15 on a new one than to buy a new engine. YourMechanicâs technicians bring the dealership to you by performing this job at your home or office 7-days a week between 7AM-9PM. You’ll just end up periodically replacing something or the other. If you can’t tell if the coolant in the radiator is flowing, shine a flashlight inside so you can see it better. If the thermostat is stuck closed, antifreeze won’t flow from the radiator, resulting in the car overheating. Favorite Answer. Thank you! To find out what's wrong with your car's heating system and what you can do to fix it, you first need a basic read of the situation. When you start your car after it has been sitting, such as in the morning, the thermostat is closed and remains that way until the coolant builds to a specified temperature. I'd and use William again. Unplug the electrical connector from the sensor if your car has one. However, this usually comes with other issues, such as a rough idle. When you are concerned about the routine maintenance of your car, it is natural to get to a point where you will ask yourself, what is a thermostat? wikiHow, Inc. is the copyright holder of this image under U.S. and international copyright laws. A sticking thermostat is a serious problem. wikiHow, Inc. is the copyright holder of this image under U.S. and international copyright laws. A thermostat regulates the flow of coolant flowing to the engine. A car's heater does not generate heat if the coolant level is low or restricted by buildup, if the water pump failed or if the thermostat is broken. wikiHow, Inc. is the copyright holder of this image under U.S. and international copyright laws. You may not know that this is happerning depending on where the temperature sensor is located. This image may not be used by other entities without the express written consent of wikiHow, Inc.