Fuel Pressure Sensor Buyer’s Guide
- A fuel pressure sensor is a small electronic device that is part of a car’s electronic returnless fuel system. This sensor feeds fuel pressure data to the powertrain control module or the PCM.
- A faulty fuel pressure sensor will cause a car to consume more gas than usual.
- A damaged sensor may cause the fuel to leak.
- The engine may feel alright and run but the condition of your sensor will only worsen.
- The price range of a fuel pressure sensor may vary depending on the car model, year, and make. OE or Original Equipment replacements usually cost around $20.
What is a fuel pressure sensor?
A fuel pressure sensor is a small electronic device that is part of a car’s electronic returnless fuel system. This sensor feeds fuel pressure data to the powertrain control module or the PCM. The PCM serves as the main computer of an automobile.
The fuel pressure sensor is also responsible for analyzing the pressure of the fuel that is inside the rail of the fuel pump assembly. This is an electronic device which calculates the fuel pressure, then sends the fuel tank pressure sensor readings to the PCM.
How does a fuel pressure sensor work?
The PCM will know the exact amount of fuel to feed the engine with the information it receives from the fuel pressure sensor. It senses the amount of fuel in the fuel rail by reading the internal pressure of the rail as it sends an electronic message to the PCM.
Fuel pressure contained by fuel sensors can run between 25 to 60 pounds of pressure depending on the vehicle and the manufacturer. All fuel-injected vehicles have fuel pressure regulators and the regulator on the fuel rail will contain the fuel injectors. There is a main fuel line from the fuel tank to the fuel rail and a return fuel line from the fuel pressure regulator.
The fuel pressure regulator uses a diaphragm and spring combination within its housing with a vacuum source on the top side of the diaphragm to counteract the spring pressure when high demand dictates that higher fuel pressure is necessary. This is a critical process as it enables the engine to receive just enough fuel to operate properly while lowering evaporative emissions.
Where is the fuel rail pressure sensor located?
The fuel pressure sensor is located along a vehicle’s fuel rail, and is part of the fuel pump assembly. It is mounted either on top of the tank or inside the tank. As mentioned above, it is a part of the EVAP or the evaporative emissions system.
Electronic returnless fuel systems reduce evaporative emissions from automobiles by giving the engine a precise amount of fuel to make it run. Furthermore, this system prevents excess fuel from evaporating in the fuel line.
Fuel vapors are supposed to be contained in the EVAP system, and leaks can be emitted into the atmosphere. The sensor is connected to the engine computer and if the sensor detects a leak or fails to function, it illuminates a light that signals that the engine has to be checked.
What happens when the fuel tank pressure sensor goes bad?
How do you know if your fuel rail pressure sensor already needs changing? Here are five symptoms of a faulty fuel tank pressure sensor.
Decreased fuel efficiency
A faulty fuel pressure sensor will cause a car to consume more gas than usual. Since the main function of the fuel pressure sensor is to control the pressure of fuel that gets delivered to the engine, the fuel will move in a very sluggish manner once there is very low pressure, and there will also be negative consequences when there’s too much pressure.
A fuel pressure regulator has seals on both sides. A damaged sensor may cause the fuel to leak. There can be an opening in the seals once they’re damaged, and this may cause the fuel to pass through. Unfortunately, seals are very much prone to wear and tear overtime and they don’t usually last the life span of the vehicle.
This is one of the first symptoms of a bad fuel pressure sensor that car owners will notice. As you step on the gas pedal, the car may accelerate but sluggishly. And no matter how hard you step on the accelerator, the car won’t just go fast enough.
Together with a problematic fuel pressure sensor, in this case, may be a faulty fuel injector. Dirt and debris can build on the tips of the fuel injectors, which can clog the small holes that spray fuel to the combustion chamber.
Engine won’t start
An engine that won’t start can be caused by a myriad of problems, and one reason could be a damaged fuel pressure sensor. If the sensor is faulty, the right amount of fuel will not be fed to the combustion chambers, hence, the engine will have difficulty starting.
Black smoke from the tailpipe
It can be alarming to see black smoke coming out of your car. This can be an indication of a problematic fuel tank sensor. The air-fuel ratio may be incorrect, so the engine ends up burning more fuel than usual. More fuel burned could result in thicker gas coming out of the exhaust system.
Can you drive with a bad fuel pressure sensor?
A faulty fuel pressure sensor could trigger the check engine light to illuminate. The engine may run but the condition of your sensor will only worsen. Furthermore, your engine might start stalling even when at idle. Having a car in this condition will only make driving difficult and dangerous.
How much does a fuel tank pressure sensor cost?
The price range of a fuel pressure sensor may vary depending on the car model, year, and make. OE or Original Equipment replacements usually cost around $20.
Proper Replacement Procedure for Your Car’s Faulty Fuel Pressure Sensor
Located along your vehicle's fuel rail, a fuel pressure sensor ensures that the engine is fed with the exact amount of fuel that it needs. It helps lessen the toxic emissions of your car by making sure that there's no excess fuel in the fuel line. It's a weak component that's extremely prone to irreparable damage. Once it goes bad the only thing you can do is to get a replacement. One of the most common symptoms of a faulty fuel pressure sensor is rough engine performance. Check out the following tips for additional guide when replacing the fuel pressure sensor:
Difficulty level: Moderate
Things that you'll need:
- Jack stands
- Ratchet and socket set
- Owner's manual
- Replacement fuel pressure sensor
Step 1: Prepare your work area. Since you're dealing with your car's fuel system, you have to make sure that you're parked on a well-ventilated place. Keep well away from sparks, open flame, and flammable chemicals to ensure that there are no fire hazard while you're doing this replacement procedure. It's also highly recommended that you keep a fire extinguisher near you just in case a need for it arises.
Step 2: Turn off the engine of your car and let it cool down for a few minutes before working on it.
Step 3: After the vehicle has completely cooled down, you can now relieve the pressure of the fuel system. Relieving the pressure is an important procedure when it comes to working on the fuel system of your car. This helps avoids the fuel from spewing out and putting your safety at risk.
Step 4: Locate the fuel pressure sensor on your vehicle. It's usually hard to see and access this component, so if you're having a hard time finding it, consider checking out your owner's manual.
Step 5: Remove the components that may get in the way of its removal. This may vary for every vehicle, so keep the owner's manual with you for additional helpful instructions regarding this procedure. Always keep in mind that you should handle all components with care to avoid harming any part.
Step 6: After you got all the obstructing components out of the way, you should be able to access the fuel pressure sensor without any problems. Disconnect the wirings that are attached to it by simply pulling it off using your hands.
Step 7: Detach the faulty fuel pressure sensor from its mounting place using the appropriate ratchet and socket set. After removing all its fasteners, pull it off and set it aside.
Step 8: Place the replacement c over the same place where you removed the faulty one.
Step 9: Secure it in place with the same fasteners that you detached from the old fuel pressure sensor. Tighten them up according to the manufacturer's specifications.
Step 10: Reattach all the other automotive parts in their proper places.
Step 11: Take your vehicle out for a test ride to see if the new fuel pressure sensor is working as it should be.
Replacing the fuel pressure sensor of your vehicle may take around two hours to finish if done properly.