Jeep Wrangler Temperature Gauge Fluctuates

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Last Updated on June 30, 2022

The Jeep Wrangler is a sport utility vehicle that excels in off-road adventures. You can either go on family outings or to summer camps, and you’ll have a great time.

However, like anything, there are drawbacks and the vehicle may start to break down over time. You may notice that the temperature indicator on your Jeep Wrangler fluctuates.

Although that’s not a common issue, some Jeep Wrangler owners have indeed reported their temperature gauge acting strangely. 

This component travels up and down at a variable rate, and it is a solid indicator that there is an issue that needs to be addressed right away before your Wrangler suffers more costly damage.

Jeep Wrangler Temperature Gauge Fluctuates

What is the source of this problem?

This could occur for various reasons, and you will need to establish the proper evaluation prior to administering the solution. 

Thermostat Issues

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When attempting to figure out what’s wrong, this is among the top areas that you should check. The thermostat is in charge of maintaining the engine’s optimal temperature by controlling it.

This temperature varies from 180°F to around 200°F. Whenever the engine hits this maximum temperature, its thermostat releases, allowing coolant to enter, cooling the engine and maintaining ideal temperatures.

This could happen when the thermostat is jammed in a closed position. So when engine temperature rises over a certain point, the defective thermostat closes and prevents coolant from entering. 

This causes the engine to be overheated and may eventually fail also if your thermostat is basically stuck on the “open” setting. The coolant is discharged first before the engine gets the proper operating temperature whenever this occurs. 

As a response to that, the emissions rise, and engine wear accelerates. Its temperature gauge will indeed be set to cool all the time.

Radiator Fan Not Working

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A damaged radiator fan might be causing your temperature gauge to malfunction. When this fails, your engine temperature does not adjust properly, resulting in the engine being too overheated. 

This can result in long-term mechanical issues, but you always replace the malfunctioning radiator fan as soon as possible before it creates any more damage. 

Air bubbles

Another typical reason for the temperature gauge malfunctioning is when air gets caught within the engine cooling system. 

Its often accompanied by a gushing sound. Wranglers are intended to contain an internal system for getting rid of the rest of such tiny bubbles, but that doesn’t usually function.

If an air pocket is present, the engine temperature increases while the vehicle is still and revving but drops as the car resumes movement.

The temperature gauge will move irregularly rather than staying in one spot. Now take the radiator cap off and set the front area of the car on a slope or at an angle to repair or replace any trapped bubbles. 

Allow the car to idle for a bit after restarting it. Squeeze the radiator pipe several times when the engine warms up, and the hose softens.

You may hear a burping sound when the air bubble is deflated. If the problems continue, replace the radiator cap and test the car. The issue should be resolved by burping, and the temperature gauge should be back to normal.

Cylinder Head Gasket That Is Leaking

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An overheating engine is the most common cause of this condition. As a result of the cylinder head gasket being damaged, coolant leaks and mixes with the oil.

The produced combination is insufficient for adequate engine lubrication. If the issue is not resolved soon, the engine will be permanently damaged, and it may be necessary to consider replacing the engine.

Temperature Gauge That Isn’t Working

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Lastly, it’s conceivable that your gauge is having issues simply since it’s malfunctioning. And to fix it, you might need to make sure to check if the temperature sensor is functioning properly or not. 

If not, you’ll have to acquire a temperature sensor and see if there’s a difference. However, pressure sensors really aren’t prohibitively costly, with a decent quality one costing around $10 or more.

The Summary

A vehicle’s engine must now operate at a consistent temperature, and any significant variations can damage it in various ways.

Thankfully, any problem that might create unpredictable behavior of the vehicle’s temperature gauge is affordable to repair and won’t require long.

So it is worth noting that detecting anomalous temperature gauge performance necessitates quick action since most of these faults can create major damage, resulting in hefty repair expenditures.

Frequently Asked Questions

Is it possible to drive with a defective coolant temperature sensor?

Driving a car with a defective coolant temperature sensor is conceivable since the control system resorts to a stable value. 

The coolant sensor in a car is a crucial component employed by the engine management system. It directly impacts the cooling and fuelling of the engine and, hence, how the engine operates.

What is the cost of replacing a coolant temperature sensor?

The typical cost of replacing an engine temperature sensor is around $150 and $190. Labor costs around $100 per hour, while components cost $65 or more per hour.

How long does it take for a coolant temperature sensor to fail?

For around 100,000 miles and your engine coolant temperature sensor should be frequently changed. If the engine cooling system is not correctly maintained, the sensor may fail considerably sooner.

Can the thermostat influence idle?

No, an open thermostat would just allow the engine to stay cool all the time, leaving your heater ineffective.

How can you know whether your thermostat is turned on?

Start your car’s engine, then let it idle for a few minutes. Examine the radiator filler neck to determine if the coolant is flowing. 

That it shouldn’t be flowing at this moment since your vehicle has not achieved the operational temperature that would allow the thermostat to open. 

If you see that the coolant is running, the thermostat valve seems to be open.

About the Author: Brian Silvestro

Brian Silvestro is the founder and chief editor of OffroadersArena. He spends his free time tending to his BMW iX SUV and explaining its merits to anyone who'll listen.

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