What happens when an oil temperature sensor goes bad?

When an oil temperature sensor goes bad, it can cause a variety of issues with your vehicle's engine and performance. The oil temperature sensor is a critical component that monitors the temperature of the engine oil and relays this information to the vehicle's computer system. If the sensor fails, it can lead to problems ranging from decreased fuel efficiency to engine damage.

Symptoms of a Bad Oil Temperature Sensor

Some of the most common symptoms of a malfunctioning oil temperature sensor include:

• Erratic or inaccurate temperature readings: The vehicle's dashboard display or computer may show wildly fluctuating or incorrect oil temperature readings.


• Poor fuel economy: A bad oil temperature sensor can cause the engine to run inefficiently, leading to decreased fuel efficiency.


• Engine performance issues: The engine may experience problems like hesitation, stalling, or reduced power due to the inaccurate temperature data.


• Check engine light illumination: The vehicle's onboard diagnostics system may detect the sensor failure and trigger the check engine light.


• Engine overheating: In severe cases, a faulty oil temperature sensor can cause the engine to overheat, potentially leading to serious damage.

If you notice any of these symptoms, it's important to have your vehicle's oil temperature sensor inspected and replaced if necessary.

Causes of Oil Temperature Sensor Failure

There are several common reasons why an oil temperature sensor may fail, including:

• Wear and tear: Over time, the sensor can become worn or damaged due to the harsh operating conditions of the engine.


• Electrical issues: Problems with the wiring or connectors can disrupt the sensor's ability to accurately measure and transmit the oil temperature.


• Contamination: Exposure to oil, dirt, or other contaminants can interfere with the sensor's function.


• Extreme temperatures: Prolonged exposure to very high or low temperatures can cause the sensor to malfunction.

Replacing a faulty oil temperature sensor is generally a straightforward repair, but it's important to have it done by a qualified mechanic to ensure the new sensor is properly installed and calibrated.

Preventing Oil Temperature Sensor Failure

To help extend the life of your vehicle's oil temperature sensor and avoid potential issues, consider the following tips:

• Regular oil changes: Keeping up with the recommended oil change intervals can help prevent contamination and wear on the sensor.


• Cooling system maintenance: Ensuring the cooling system is functioning properly can help regulate engine temperatures and protect the sensor.


• Avoiding extreme conditions: Try to minimize exposing the vehicle to very hot or cold environments, which can stress the sensor.


• Prompt repairs: If you notice any symptoms of a failing oil temperature sensor, have it inspected and replaced as soon as possible to prevent further damage.

By understanding the importance of the oil temperature sensor and taking proactive steps to maintain it, you can help keep your vehicle running smoothly and avoid costly repairs down the road.

What are the symptoms of a bad engine oil temperature sensor?

Typical symptoms of a failed OTS unit or circuit:

• Fault codes logged.
• Engine runs rough when cold but improves as heated.
• Hesitation at light pedal low RPM.
• Surging at constant low to mid RPM.
• Engine may not re-crank when hot. Engine may need to cool prior to restarting.

How much does it cost to fix an oil sensor?

The average cost to replace an oil pressure sensor is between $100 and $220, including parts and labor. The sensor itself typically costs between $20 and $80, while labor can range from $50 to $120 or more, depending on the vehicle and mechanic. 
You can watch this video to learn about the symptoms of a bad oil pressure sensor: 46sEasyAutoFixYouTube · Dec 21, 2021
Cost breakdown

• Parts: The oil pressure sensor usually costs between $20 and $80 for most common vehicles, though prices can be higher for aftermarket or original equipment manufacturer (OEM) parts. Luxury or high-performance vehicles may have more expensive parts. 
• Labor: Labor costs are generally between $50 and $120, but can vary based on the shop's hourly rate and location. Some repairs can be more complex if the sensor is in a hard-to-reach spot, increasing labor time and cost. 
• Total: Most estimates fall in the $100 to $220 range, with some high-complexity jobs potentially costing more. 

Factors that influence the cost

• Vehicle make and model: The price varies depending on your car's make, model, and year. 
• Part quality: OEM parts are often more expensive than aftermarket parts. 
• Labor rates: Dealerships typically charge more for labor than independent mechanics. 
• Accessibility: If the sensor is difficult to access (e.g., it requires removing other engine parts), the labor cost will increase. 

Important note

• Replacing a faulty sensor promptly is crucial to avoid potentially catastrophic engine damage from loss of oil pressure. 

Can I drive with a bad temperature sensor?

You should not drive with a bad temperature sensor, as it can lead to overheating and serious engine damage. While your car might seem to run okay, a faulty sensor can also cause poor performance, lower fuel efficiency, and other issues by sending incorrect information to the engine's computer. It is best to have it replaced as soon as possible. 
This video explains the symptoms of a bad engine coolant temperature sensor: 54sDr. Cool YouTube · Aug 19, 2023
Risks of driving with a bad temperature sensor

• Engine overheating: The most significant risk is that you won't be warned of an overheating engine, which can cause irreversible damage. 
• Poor engine performance: The engine's computer might misinterpret the temperature, causing it to run rich (using too much fuel) or lean (using too little fuel), which can lead to a variety of performance problems. 
• Reduced fuel efficiency: By incorrectly adjusting the air-fuel mixture, the sensor can cause you to use more fuel than necessary. 
• Potential for more damage: The poor performance and overheating can strain other engine components and lead to more expensive repairs down the line. 
• Check engine light: The "check engine" light will often illuminate, indicating a problem with the sensor system. 

This video demonstrates how to replace an engine coolant temperature sensor: 1m8020 AutomotiveYouTube · Mar 2, 2025
What to do instead

• Inspect your coolant: Check the coolant level in the reservoir to make sure it's full. If it's not, add the correct type of coolant. 
• Get it repaired immediately: It is strongly recommended that you get the sensor replaced by a mechanic or as soon as you can. 
• Drive with caution: If you absolutely must drive, do so for the shortest distance possible, keep a close eye on the temperature gauge and any warning lights, and avoid heavy acceleration or stop-and-go traffic. 

What happens if you drive with a bad oil sensor?

Short answer: driving with a faulty oil pressure sensor is risky because it removes an early-warning signal for low oil pressure and can let an engine-damaging condition go unnoticed.