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Jeep Temperature Gauge Goes Up And Down : [ Reasons & Fix ]

Jeep Temperature Gauge Goes Up And Down : [ Reasons & Fix ]

If you have been driving on the roads lately, you may have noticed that some Jeeps are continuing to have issues with the temperature gauges. From 2014 to 2018 Jeeps, the gauges include an eInk display, which displays the temperature in a traditional analog temperature gauge.

However, some Jeeps still display the temperature on a digital screen, making it harder to read the temperatures.

Why Does My Temperature Gauge Go Up and Down?

That’s probably because your sensors are loose and need to be tightened. Learn how to do that, and you’ll have a more reliable gauge that temperature changes won’t throw off.

Additionally, this could also mean some parts of your cooling system are faulty or are clogged and need to be checked by a mechanic.

Signs the Cooling System is Faulty

Your car’s thermometer functions as a precision temperature gauge similar to a thermostat in a household. When the car engine is turned on, an initial surge of coolant flows through the radiator and out the other side to the engine block.

1. Black Smoke

The reason is simple: If a car doesn’t have enough coolant to handle the heat produced by the engine, the cooling system will eventually boil the coolant.

The black smoke signifies that your engine is overheating and the oil is now being burnt up. Check the engine compartment to see if the coolant is cool to the touch or if the coolant is leaking from the heat exchanger.

2. Regular Overheating of Your Engine

This is the first sign that your cooling system is not working efficiently. A good system should let your drive up to 600 miles without having overheating problems.

Check with your mechanic to avoid extra damage to your engine that might be costly to repair.

3. Jumpy Temperature Readings

In case your notice unusual readings on your temperature gauge, say the reading is high or low when it is supposed to be a bit higher; that is a faulty temperature sensor.

It would be best to inquire with your mechanic to pinpoint the problem as a normal outside temperature could cause it.

4. Fuel Efficiency

If you notice an increase in your car’s fuel consumption, this could be caused by a faulty cooling system. Your mechanic will look at the whole system and ensure that it is working right, and if it doesn’t change, you have to find another problem for your high fuel consumption.

5. Check Engine Light

Your dashboard has a check engine warning sign. If this sign comes on, there could be several reasons, such as a faulty cooling system.

This is possible in newer models, which have sensors that detect a fault in the cooling system.

Cause for a Jumpy Temperature Gauge

There are several reasons for this phenomenon happening to jeep vehicles and other SUVs in the market. Some of the common causes are the following;

1. Thermostat

The thermostat is a small part of your engine. That part controls the opening and closing of the coolant flow to the radiator. When the thermostat is bad and stays open, the water will not circulate in the engine, and thus the engine will not be cooled.

The temperature gauge will read high because there is no coolant in the engine to cool it. When it is cold outside and the engine is not getting any heat, the temperature gauge will read low because the coolant is still cold.

How To Fix Your Thermostat?

You won’t need to remove the thermostat to make this inspection. You have to remove the duct that connects the air conditioning unit to the radiator.

This duct is located right next to the air conditioning unit. You can then see your thermostat.

One way you can determine if your thermostat is stuck open is simple. Just open the radiator cap and start your engine; if your coolant starts moving immediately, the thermostat is stuck open.

On the other hand, if the coolant doesn’t move after running your engine for 10-30 mins, the thermostat is stuck shut.

Replacing a thermostat is a simple procedure. If you don’t know how to do it yourself, it is advisable to take it to your mechanic, who will replace it in less than 20 mins.

2. Air Bubble in the Cooling System

Air bubbles will tamper with your temperature gauge, causing the reading to go up and down. This air is usually trapped in the radiator, and you can hear a gurgling sound when the engine heats up.

It is easy to let the air trapped in your cooling system out. You have to remove the radiator cap and start your engine, wait for a few minutes for the coolant to heat up, find the hose that connects to the radiator from the top side and firmly press it in and out several times.

A distinct burping sound will be heard from the open radiator as the trapped air is released. You can keep doing this several times to ensure all the bubbles in your cooling system have been expelled.

3. Faulty Cylinder Head Gasket

There are usually a few tell-tale signs when there is a problem with the cylinder head gasket as a cooling system problem. First, the engine’s coolant level will begin to rise.

The coolant will also begin to overheat. Your vehicle will also exhibit a lack of power. The engine will make an unusual noise, particularly when you are accelerating.

A faulty gasket will also cause damage to your engine that may not be reversible if not detected properly. When the gasket is blown, coolant and the oil that lubricates the engine usually mix up, causing a messy mixture that does not perform its functions efficiently.

The replacement of your gasket will usually require draining your oil and coolant before replacing the gasket and then filling up the two ones again. This is to avoid any more damage to your engine.

4. Faulty Radiator Fan

The radiator fan is crucial for cooling the coolant with the help of your radiator. There are different types of radiator fans fixed on vehicles today, with most being electrically controlled by a sensor.

These electric radiators are good but can get tricky when they start to fail because of a blown fuse or a faulty heat sensor.

The faulty fan should be replaced immediately to avoid damage to the engine and further repair costs down the line.

5. Leaking Radiator

Over time a radiator can develop a leak. If your car is leaking coolant, you see a pool of coolant under the car, or you see steam coming out of your engine, it is probably a leaky radiator.

Left unmanaged, it can cause major engine damage, and your car will no longer be safe to drive. This can be catastrophic if you are driving, causing an accident.

A radiator is a major component of your car’s cooling system, but it’s also the first to look for problems when your car isn’t getting cool enough. There are some DIY methods that you can use to fix a leaking radiator, but the fix will only be temporary.

A leaking radiator will have to be fixed as soon as possible to avoid more damage and ensure a permanent fix.

6. Temperature Gauge

Your temperature gauge might be faulty hence the jumpy reading on your Jeep. This is usually because of a failed fuse or a wiring problem. If you run the above tests and corrections and still face the same issue, you will have to check your temperature gauge.

You will have to find an expert who will perform tests on your gauge and determine if it needs repair or a whole repair.


The Jeep performance gauge helps a driver better understand a car’s performance. The gauge’s red bar represents the current temperature, and the green bar indicates how well the Jeep is running.

Each team’s score is a ratio of the red and green bars. The lower the score, the better the Jeep is performing. If you experience temperature gauge problems, you should have your Jeep checked to avoid more damage and identify the problem before it gates costly to repair.