5 Symptoms of a Bad Fuel Rail Pressure Sensor
In diesel and some gasoline vehicles, the fuel rail pressure sensor (not to be confused with the fuel tank pressure sensor) monitors the supply to the injectors. If this component fails, you’ll experience reduced performance without any warning lights coming on.
But what happens if the sensor fails, and how do you detect it? Read this article to understand the signs of a bad fuel rail pressure sensor, what causes it to fail, and how much it might cost to replace it.
What does a fuel pressure sensor do? The purpose of this sensor is to monitor the fuel pressure in the fuel rail. Once the sensor detects this information, it sends the data to the Engine Control Unit.
From there, a computer analyzes the data and makes any necessary changes to the fuel injection timing and amount of fuel injected. This results in optimal engine performance depending on the current driving conditions.
The Engine Control Unit then indicates the exact amount of fuel required by the engine. When more fuel is injected into the combustion chamber than necessary, fuel economy suffers.
What is a Fuel Pressure Sensor?
Furthermore, the useful life of emission-related components is also shortened, releasing excess carbon emissions into the atmosphere. Most vehicles on the road today are built to be as environmentally friendly as possible, so the fuel rail pressure sensor is a critical component that must keep working at all times.
The 5 Most Important Symptoms of a Defective Fuel Pressure Sensor
If there is a problem with the fuel rail pressure sensor, the engine control module will not be able to function properly. Here are the 5 most common signs of a faulty fuel pressure sensor.
1) Check Engine Light
If your fuel rail pressure sensor is bad, you may experience a “Check Engine Light” warning light on your dashboard. This light comes on when the engine control unit detects a problem with your vehicle that affects the engine in some way.
This doesn’t necessarily mean that the engine itself is at fault, it just means that something else in your vehicle is preventing the engine from running properly. P0190, P0191, P0192, P0193, and P0194 are the most common DTC codes that indicate a fuel rail sensor problem.
2) Engine is difficult to start
If the fuel rail pressure sensor is bad, the ECU will not send the correct amount of fuel to the engine. This will make the vehicle difficult to start.
If this is the first time you experience this problem, it will probably take a few tries before the engine starts. However, as the problem gradually worsens, it will take more tries to resolve the issue. In many cases, the engine will start and then immediately shut off again. Eventually, it will not start at all.
3) Weak Acceleration
If your vehicle does not accelerate as expected when you step on the accelerator, it may be due to a faulty fuel pressure sensor. The engine control unit receives inaccurate information from the sensor and cannot properly send signals to the fuel system, which means it does not know how to meet the engine’s fuel demand.
4) Stalling
If the fuel rail pressure sensor continues to deteriorate, it can cause your engine to stall. You’re driving your car and it suddenly stalls out. It may even go out when idling.
This will make driving very difficult (and dangerous), and should motivate you to do something about it. If you determine that the sensor is the culprit, immediately take your vehicle to your nearest auto repair shop and have the sensor replaced.
5) Poor fuel economy
When your fuel pressure sensor isn’t working properly, you’ll notice a significant drop in fuel consumption and gas mileage. The engine control unit is either sending too much or too little fuel through the fuel lines to the combustion chambers. You’ll soon find yourself making more trips to the gas station and spending more money. Large vehicles are usually the ones that experience the most fuel economy loss.