The main reason why car temperature gauge goes up and down while driving is because something is not working properly in your car’s cooling system. It could be the radiator fan, water pump, thermostat valve, coolant, or the gauge itself. To fix either of these issues, we’d advise that you engage a proven auto mechanic.
What causes a temperature gauge to fluctuate?
One common cause is a defective thermostat, a component that is inexpensive and easy to replace. Other causes of a fluctuating temperature gauge are a failing radiator fan, insufficient coolant level and a leaking cylinder head gasket. A failing radiator fan will be erratic.
Why does my coolant temp drop?
Thermostat Failure Thermostat valves can fail in one of three ways: open, closed or stuck halfway. A stuck-open thermostat will constantly send coolant through the radiator, regardless of its temperature, causing coolant temperatures to drop and the heater to malfunction while traveling down the road.
What are the signs of a bad thermostat?
Symptoms of a Failing Car Thermostat
- The temperature gauge reads high and the engine overheats.
- The temperature changes erratically.
- The vehicle’s coolant leaks around the thermostat or under the vehicle.
What are the symptoms of a bad thermostat?
Leakage from the mounting surface. Appearance: Seepage, drips or large coolant bleed marks on or around the mounting surface or on the housing.
- Rust and corrosion. Appearance: Rust and corrosion on the surfaces of the thermostat.
- Deposit build-up.
- Map-controlled thermostats.
How do I check if my thermostat is working?
Check the screen: Check the screen of the thermostat and make sure that it is lighted. A blank or unlighted screen could indicate a thermostat failure. Check the batteries: Many modern thermostats rely on battery power to operate. If the screen is blank or unlighted, a battery change could solve the problem.
What happens when a thermostat goes bad?
Because your thermostat controls temperature of fluids from the radiator hose, a bad thermostat will cause your car to overheat. When the engine temperature has reached the operating level, it should allow coolant to flow to the engine and regulate the heat.
How can you tell if your thermostat is open?
Start your car’s engine and allow it to idle. Look through the radiator filler neck to see if the coolant flows. At this time, it should not be flowing as your car has not reached the operating temperature to cause the thermostat to open. If you find the coolant is flowing, it means the thermostat valve is open.
How long can you drive with a bad thermostat?
You car can drive when engine condition is cool till it achieve the max temperature. If the thermostat valve of your car is broken or not working properly there may maximum chances of engine over heating. After engine over heating the car stops and gets off. Your car won’t start until the engine cools down.
What are signs of a bad thermostat?
There are several common symptoms associated with a bad or failing thermostat that will alert you that service is due.
