fuel pressure sensor

Fuel Rail Pressure Sensor Symptoms, Function & Replacement Cost

In Engine by Magnus Sellén3 Comments

fuel pressure sensorThe fuel rail is responsible for the supply of fuel to the combustion chamber.

This sensor ensures that the engine cylinders of your car receive the right amount of fuel at the right pressure. The sensor calculates the pressure and sends the data to the ECU.

The ECU then decides on the correct fuel supply measure. Any malfunction of the pressure sensor in the fuel supply can interrupt the proper flow of the engine and cause the engine’s performance to collapse.

Signs of a Bad Fuel Pressure Sensor

The sensors in modern cars are susceptible to damage from the constant exposure to pollutants such as dirt, dust and heat.

The fuel rail sensor is one such sensor that can be damaged quite easily. If this is the case, you should feel some symptoms of its failure, which should force you to use the services of a professional mechanic.

1. Difficulty Starting your Car

As already mentioned, the fuel rail supplies the cylinders with the same fuel. The mechanism that ensures that the fuel rail is efficient is the fuel rail pressure sensor. If the fuel rail sensor malfunctions, it sends incorrect information to the ECU, which changes the settings, causing the fuel supply to be inadvertently interrupted and your car to take longer to start.

2. Poor Engine Performance

A defective fuel rail pressure sensor will affect the performance of your ride. If you try to accelerate, your engine will not have an efficient fuel supply, resulting in poor acceleration. Not only that, if the fuel pressure sensor is faulty, it may output too little information to the ECU, which in turn may increase the amount of fuel being fed into the engine. As a result, you lose fuel and have to fill your car’s tank more frequently.

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3. Check Engine Light

This is probably the first symptom you notice. The check engine light is an indication that something is going wrong in your engine that needs immediate attention. This light is triggered by the ECU, which detects the defective fuel rail pressure sensor and acts accordingly. Whenever this light comes on on your dashboard, you should make a trip to the nearest mechanic.

4. Stalling Engine

Improper supply of fuel to the engine will cause an unexpected stall. No matter what you try, the engine will not start again. If this happens frequently, the fuel rail pressure sensor is not working properly enough to send the correct information to the vehicle’s onboard computer.

If the ECU is unable to make adjustments, your vehicle is at high risk of developing unnecessary problems.

Cleaning the Fuel Rail Pressure Sensor & Connector

Each sensor must be properly treated every few thousand kilometers to ensure its efficiency. The fuel rail pressure sensor is one such sensor, located under the intake manifold and just touching the fuel rail. Given its location, you can imagine the amount of heat the sensor must absorb and the vibrations it must feel. So the sensor will eventually fail. Cleaning the sensor and the connector can refresh its functions.

Things you will need:

Plastic Bag

Remove the Sensor

Removing the sensor actually requires some mechanical work. A few wrenches, open-ended spanners and screwdrivers need to be used to save the day. However, if you are reading this part of the article in the first place, you must have some interest in keeping your sensor alive a little longer. The first thing you need to do is to disconnect the electrical plug that goes into the fuel rail sensor. The second thing is to remove the vacuum line coming from the engine. When all these parts are disconnected from the fuel rail pressure sensor, you can try to pull it out.

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Use Cleaner for Cleaning

There are two ways to clean a sensor, one is conventional with alcohol or ethanol, while the other requires the use of a special cleaner. However, both methods clean the sensor equally well. Start by cleaning the sensor with a clean cloth to remove fresh dust. When the dust is clean, place the sensor in the plastic bag and add some cleaner to help rub off the contaminants. Then allow the sensor to dry. It may take longer to dry if you use a cleaner because it contains a number of chemicals.

Reinstall the Sensor

As soon as the fuel rail pressure sensor has dried, you can install it again. Be sure to clean the end of the electrical connector and the vacuum line before connecting it to the sensor, otherwise your hard work will be in vain. Follow the procedure you used when you removed the sensor to reinstall it.

Testing and Repairing the Sensor

When you have finished installing the system, start your vehicle and check the dashboard for the check engine light. If it is still lit, you must use an error code scanner to reset the light. Error code scanners or OBD2 scanners are commonly found on the market. They are relatively cheap and practical for a home mechanic, so you should consider buying one if you don’t have one yet.

Restart your car after resetting the check engine light. If it comes back on, you should see the mechanic, as the problem may be more serious. A mechanic can only work to a certain degree. The sensor is an electrical component that can easily become defective; indeed, so bad that it cannot be repaired. In such cases, you need the mechanic to replace your older sensor with a new one.

Fuel Pressure Sensor Replacement Cost

The fuel rail pressure sensor may be a small car part, but it is extremely valuable and therefore very expensive. A new sensor will cost you $120 – $150, depending on your car and model year. The older the car, the more expensive the part will be.

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In addition, the mechanic will charge you for the labor cost, which is the money for his hard work. These can range from $80 to $100 due to the difficult location of the fuel sensor.

Hello I'm Magnus, the owner and the writer of this website. I have been working with cars since I was 16 and I'm specialized with in-depth Automotive diagnostics. Also been driving drifting for the last 6 years. I'm here to give you answers to all your automotive questions and I hope that you enjoy our content.

3 thoughts on “ Fuel Rail Pressure Sensor Symptoms, Function & Replacement Cost ”

  1. I have some challlenges with my Cx7 mazda suv. Hence complaining fuel rail sensor. Whats the location of the sensor? Thanks.

  2. Can a bad fuel rail sensor cause a misfire I’m having a misfire in cylinder 1 and cylinder 2 I change all spark plugs spark plug wiring all coils and I’m still having a misfire I also changed the fuel rail

  3. I have a 2005 mustang v6 when i accelerate i get what it seems to me would be a miss but have replaced wires plugs coil what is your advice or diagnosis

  4. Due to a very high demand and high ammount of comments, you have to wait for some time for your car questions to get answered. If you want to get fast answers from a certified master technician you can ask your questions here:
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