5 Signs of a Bad Fuel Rail Pressure Sensor (& Replacement Cost)

The fuel pressure sensor ensures the pressure in the fuel rail is correct. Here's how to tell if your sensor is bad and how much it costs to replace it

Fuel Pressure Sensor E1609977575722

The fuel rail is responsible for the supply of fuel to the fuel injectors.

The fuel pressure sensor ensures that your car’s engine cylinders 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 fuel pressure sensor can interrupt the engine’s proper fuel flow and cause the engine’s performance to collapse.

Sensors in 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.

In this article, we look at the signs of a bad fuel pressure sensor, location, function, and the replacement cost if yours is bad. First, let’s take a look at the signs to look for:

The most common symptom of a bad fuel pressure sensor is difficulty starting your car together with a check engine light on your dashboard. You may also notice signs like poor engine performance or a stalling engine while driving.

Here is a more detailed list of the 5 most common symptoms of a bad fuel pressure sensor.

Bad Fuel Pressure Sensor Symptoms

1. Difficulty Starting your Car

Difficulty Starting 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 takes longer to start.

2. Poor Engine Performance

Slow Acceleration Car

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.

3. Check Engine Light

Check Engine Light Reset Itself

This is probably the first symptom you will 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.

You can also read the trouble codes yourself with an OBD2 scanner.

4. Stalling Engine

Engine Stall E1609780473516

Improper supply of fuel to the engine will cause an unexpected stall. No matter what you try, the engine will often not start again. If this happens frequently, the fuel rail pressure sensor might not be 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.

5. Bad fuel consumption

Bad Fuel Consumption

Another symptom you can notice is a different fuel consumption than you are used to having. It can either be higher fuel consumption or lower consumption than usual – which might sound like a good thing. Your engine will not like this thing in the long run, though!

Fuel Pressure Sensor Location

Fuel Pressure Sensor Location

The fuel rail pressure sensor is located at the fuel rail, which is located near the intake manifold.

In some car models, the fuel rail pressure sensor can also be installed on the fuel line, but this is pretty rare.

Check somewhere under the intake manifold, and I’m sure that you will find the injectors, fuel rail, and the fuel rail pressure sensor.

Fuel Pressure Sensor Replacement Cost

The average fuel pressure sensor replacement cost is between $100 and $300. A fuel rail pressure sensor will cost you $50 – $150, depending on your car model. The labor work costs 50$ to 150$, depending on the workshop.

Car Fuel Pressure Sensor E1609977357133

You can absolutely save money by doing it yourself. Replacement of the fuel pressure sensor is often very straightforward on most car models.

Remember that you will handle fuel, though, which can ignite if you are unlucky and not cautious.

In some car models, you also have to reprogram the fuel pressure sensor and remove the trouble codes with a diagnostic tool after replacement.

Fuel Rail Pressure Sensor FAQ

What happens if the fuel rail pressure sensor goes bad?

If your fuel pressure sensor goes bad, the first thing that will happen is that you check engine light will appear on your dashboard. You can also notice strange problems with the performance of your car engine.

How can you tell if a fuel pressure sensor is bad?

You can tell that your fuel pressure sensor is bad by seeing a check engine light on the dashboard. You can also check the values coming from it with a diagnostic scanner or by measuring it with a multimeter.

How do you test a fuel rail pressure sensor?

You can test the fuel rail pressure sensor either with a diagnostic scanner or a multimeter. Connect the diagnostic scanner and check the values coming from it. Compare the values to the values you find in the repair manual. You can also check the sensor with a multimeter, but you need to get the given sensor’s right measurement values. Find out more on this video.

Can you clean fuel rail pressure sensor?

You can clean the sensor, but it is doubtful that it will make a difference. In some very rare cases, dirt can block the passage to the sensor head, which will make the sensor work again after a clean. However, in most cases, you need to replace the fuel pressure sensor.

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Written by:

Magnus is the owner and main author of MechanicBase. He has been working as a mechanic for over 10 years, and the majority of them specialized in advanced diagnostics and troubleshooting. Certified Automotive Diagnostic Technician.