How does Oil Pressure Sensor Work? | Bad Engine Oil Pressure Sensor Symptoms and Causes

The oil pressure sensor is one of the most important parts of the modern vehicle. It is used to monitor the oil pressure in the engine. The powertrain control module (PCM) of your vehicle utilizes the data of the oil sensor to control the flow of the oil. When this sensor goes bad, it generates different symptoms. This article mainly explains the bad oil pressure sensor symptoms, replacement cost, and its function.

What is an Oil Pressure Sensor?

An oil pressure sensor is a mechanical device that is used to measure the oil pressure in the engine. The engine oil pressure sensor is most commonly installed on the engine block.

Oil Pressure Sensor

The rotating parts of the engine require a proper supply of oil to work efficiently. The oil is used to lubricate the rotating parts like bearings and camshafts. When these parts rotate, their surfaces interact with each other.

When metal surfaces of the parts collide with each other, they generate rattling noise. Due to the collision of the metal surfaces, a large amount of heat dissipates. This generated heat may cause the parts to be damaged.

It is, therefore, necessary to reduce the friction between the surfaces and avoid power losses due to heat build-up. This is where engine oil plays a big role. The engine oil properly lubricates the rotating parts, makes a layer between the mating surfaces, and prevents them from colliding.

Oil must be supplied at sufficient pressure. A sufficient oil pressure ensures that the oil properly reaches all points in the engine and lubricates all the desired parts.

The vehicle contains an oil pump that pumps the oil at sufficient pressure. This pump draws oil from the oil pan to the engine head to cool and lubricate different parts of the engine. With low oil pressure, the engine can no longer lubricate effectively or maintain cooling, causing components to seize and leading to irreparable damage and high costs.

The vehicle contains an oil pressure sensor. The main function of the oil pressure sensor is to regularly monitors the oil pressure and sends this information to the vehicle’s main computer. The efficient performance of this sensor is very important for the efficient performance of the engine.

Symptoms Of a Bad Oil Pressure Sensor

When the oil pressure sensor goes bad, it gives one or more of the below-given symptoms:

  • Illuminated oil pressure light
  • Strange noises from the engine and timing chain 
  • Oil leak from oil pressure sensor 
  • Check engine light illumination
  • Wrong oil pressure gauge reading
  • Trouble codes

1) Illuminated Oil Pressure Light

The illuminated oil pressure light is one of the first symptoms of a bad oil pressure sensor. The oil pressure light is installed on the vehicle dashboard. When the vehicle’s engine oil pressure sensor monitors too-high or too-low oil pressure, it delivers a voltage signal to the powertrain control module (PCM), which analyzes the sensor information and turns on the oil warning light.

Oil pressure light

To easily identify this issue, use a pressure gauge to measure the oil pressure in the engine. If the oil pressure is normal, it means your oil pressure sensor is defective. If you don’t have a pressure gauge, then use an OBD-II scanner to determine if there is an error code related to the oil pressure sensor stored in the PCM.

Read More: Bad PCM Symptoms and Causes

2) Strange Noises from Engine and Timing Chain 

The rotating parts of the engine make contact with each other. When these parts collide with each other, they generate rattling noise and generate heat. Therefore, engine oil is used to prevent the surfaces of the rotating parts from collision. 

When your oil pressure sensor goes bad, strange noise from the engine compartment is one of the common symptoms.

Sufficient oil pressure is vital if your engine contains a timing chain that uses oil. The oil is mainly used to properly lubricate the chain and to ensure its free movement. Another reason it is important to maintain sufficient oil pressure is that the tensioner that keeps the chain’s tension in its place also constantly requires an oil supply.

A drop in the oil pressure may cause the chain tensioner to loosen, causing the chain to whip and get thrown around against different housings and pulleys. You can usually hear this noise when standing next to your car with the engine running idle.

If you hear this noise from the engine compartment, but the oil light does not come on, your oil pressure sensor may be bad. If the chain loses tension due to low oil pressure and the dash oil pressure light does not illuminate, you should change the oil pressure sensor and perform all other necessary repairs to the engine.

3) Oil Leak from Oil Pressure Sensor 

The engine oil pressure sensor is installed into your vehicle’s oil system so it can easily monitor the oil pressure. But this may lead to the oil escaping by the system’s threads or by the center of the sensor itself.

Oil Leak from Oil Pressure Sensor

Vauxhalls are famous for having this prevalent issue on some models where the oil pressure sensor leaks oil from its body’s center, which may fill the block port and spray oil into the engine compartment.

This issue can be easily diagnosed by just inspecting the sensor for oil leaks. Check the oil inside the sensor and block port by removing the block connector of the sensor. If oil is found inside the sensor or engine bay, it means you need to replace your sensor. You can check the sensor visually by ensuring that there are no signs of oil leaks from the sensor body while the engine is idling.

4) Check Engine Light Illumination

The check engine light illumination is one of the clear symptoms of a faulty oil pressure sensor. In the latest vehicle models, a computer (usually a PCM) observes the performance of the oil pressure sensor (OPS). When it observes an issue with the sensor, it turns on the check engine light to alert the driver.

check engine light

Read More: Causes and Symptoms of bad Oil Pressure Sensor

5) Wrong Oil Pressure Gauge Reading

Your car has an oil pressure gauge located on the dashboard. This gauge gets information about the oil pressure from the oil pressure sensor.

Oil Pressure Gauge Readings

As the oil sensor fails, it measures the wrong internal pressure in the oil pressure sending unit. As a result, the oil pressure gauge also shows an incorrect value.

6) Trouble Codes

In modern vehicle models, the oil pressure sensor sends its information to the powertrain control module (PCM). The PCM utilizes this data to regulate the supply of oil to the engine. When something goes bad with the oil pressure sensor, your sensor triggers a trouble code such as P0520, P0521, P0522, and P0523.

bad oil pressure sensor trouble codes

Oil Pressure Sensor Location

The exact location of the engine oil pressure sensor varies according to the vehicle model and engine location.

Oil Pressure Sensor Location

The oil pressure sensor is usually located near the bottom of the cylinder head on the engine block. In some models, it is mounted on the cylinder head.

Oil Pressure Sensor Replacement Cost 

The replacement cost of the engine oil pressure sensor varies according to the vehicle model, labor cost, and the type of brand.

The average replacement cost of the oil pressure sensor is from $40 to $260. In this cost, the labor cost is from $15 to $160, while the oil pressure sensor cost is from $25 to $100.

FAQ Section

Can I drive with a faulty oil pressure sensor?

Yes, you can drive with a bad oil pressure sensor for a short period of time. However, you shouldn’t drive with a bad engine oil pressure sensor for an extended period of time. This indicates that the engine is losing its normal oil pressure, so don’t take it lightly. As this sensor goes bad, it is recommended to replace it immediately.

The main function of the oil pressure sensor is to monitor the oil pressure in the engine and serve as a warning system if the pressure is too high or too low. In this way, it prevents engine damage due to low oil.

What is the function of the engine oil pressure sensor?

The main function of the engine oil pressure sensor is to measure the oil pressure in the oil system and sends this information to the PCM/ECM of your vehicle.

How long does an oil pressure sensor last?

The average service life of the oil pressure sensors depends on your vehicle model, driving conditions, and the oil level in your oil system. The oil pressure sensor is generally designed to last the life of the vehicle on most vehicles. It also rarely wears out. But like other vehicles’ components, it may ultimately fail.

Can a faulty oil pressure sensor put the car in limp mode?

Yes, a faulty oil pressure sensor may force the vehicle into limp mode. Limp mode is also known as a safety mode. It prevents the vehicle engine from damage. As the sensor fails, the integrity of the engine can be compromised. Therefore, your car may go into limp mode to prevent the engine from being damaged.

Can I reset my oil pressure sensor?

A normal oil pressure sensor cannot be reset. After installing the new sensor, simply start your vehicle engine. Your oil pressure light shouldn’t illuminate if everything else is fine and there are no other problems with the oil pressure or electrical connections.

What happens when the oil pressure sensor goes bad?

Failure of the engine oil pressure sensor will result in the wrong reading of the oil pressure gauge. As your PCM observes the wrong readings of the sensor, it turns on the warning light. To prevent your vehicle from severe damage, you need to fix it as soon as possible.

Can the oil pressure sensor shut off the engine?

No, an oil pressure sensor can’t shut down the engine but may stop the engine from starting if it detects too low oil pressure. If your vehicle engine is shut off and there is no oil in the oil pan, don’t start or run the engine until the inspection is complete. This is because too low or too high oil pressure may lead to engine damage.

What does low oil pressure sound like?

A drop in oil pressure may cause engine noise. Initially, you may hear tapping, ticking, or rattling noises from the rotating parts of the engine.

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