What Are the Symptoms of a Faulty Fuel Pressure Sensor?

The engine is a complex system that requires sufficient pressure to operate effectively, which is why a fuel pressure sensor is included. So, what are the symptoms of a faulty fuel pressure sensor? Is it serious when the fuel pressure sensor fails?


Symptoms of Fuel Pressure Sensor Failure
Fuel Pressure Sensor
The fuel pressure sensor is one of the most commonly used pressure transmitters in industrial practice, widely applied in various industrial automation environments, including oil pipelines, hydropower, railway transportation, smart buildings, process automation, aerospace, military, petrochemical, oil wells, electricity, shipping, machine tools, ducted air systems, and boiler negative pressure systems. Its features include easy installation and long service life.


Symptoms of Low-Pressure Fuel Pressure Sensor Failure
The low-pressure fuel pressure sensor’s role is to provide a signal to the engine control unit (ECU), which then controls the low-pressure fuel system. The ECU sends a signal to the fuel pump control unit based on the sensor's input, allowing it to adjust the electronic fuel pump as needed. If the fuel pressure sensor fails, the fuel pressure is adjusted by a pre-set value instead, typically around 6.5 bar.


Symptoms of High-Pressure Fuel Pressure Sensor Failure
The high-pressure fuel pressure sensor provides a signal that the ECU analyzes to adjust the pressure within the fuel distributor line via two fuel metering valves. If the fuel pressure sensor fails, high fuel pressure cannot be established, forcing the engine to run at low fuel pressure, which leads to a loss of power and torque.


Is Fuel Pressure Sensor Failure Serious?
Yes, a malfunctioning fuel pressure sensor can result in inadequate fuel pressure, poor fuel supply, and a lack of acceleration. In severe cases, it can even cause the vehicle to shake. It is advisable to repair or replace the sensor promptly to avoid further complications.


The fuel pressure sensor operates on the principle that pressure directly acts on a diaphragm within the sensor, causing it to displace slightly in proportion to the medium's pressure. This displacement changes the sensor's resistance, which is detected by electronic circuitry and converted into a standard signal corresponding to the pressure.