Most gasoline-powered vehicles will have a fuel rail pressure sensor, which measures the amount of pressure in the fuel rail. It then sends that information to the engine control module (ECM). The ECM then talks to the fuel pump control module to control the fuel pressure and injection timing. If your sensor isn't working correctly, your engine's performance levels will drop and you'll see an increase in emissions and unburnt fuel. If you see any of the following signs appear in your vehicle, your fuel rail pressure sensor may not be working correctly.

The Service Engine Light is On

The service engine error light is designed to light up on your vehicle's dashboard when a problem with your engine is detected.  If the light turns on, you should take your vehicle to an auto parts store or mechanic that can read the error code and tell you what specific problem you have. While the service engine light can be triggered by a wide variety of engine problems, when code P0190 shows up the fuel rail pressure sensor circuit is malfunctioning. There are several sequential codes near that value that also apply to fuel pressure problems.

You Vehicle is Experiencing Hard Starts

A hard start happens when crank the engine to start the vehicle, but the engine keeps cranking for a while before it finally turns on.  A hard start is always related to something going wrong with your vehicle's fuel supply system, and the fuel rail pressure sensor is definitely a possible culprit. If your fuel rail pressure sensor gives the wrong information to the ECM, the engine won't get enough fuel to start up correctly.

Your Vehicle Has Been Stalling

If your vehicle has been shutting down while you're driving or parked, the engine may not be getting enough fuel for the vehicle to continue running. This can happen if the ECM is getting the wrong information from the fuel pressure sensor. The sensor data is used to calculate a proper air/fuel ratio, so if the sensor passes on incorrect data your vehicle can experience unexpected stalling.

If your vehicle is experiencing any of the above symptoms, have a local auto shop, such as Precision Towing & Recovery, diagnose and fix the problem. A knowledgeable mechanic will have the expertise needed to figure out what exactly is causing the problem and to fix or replace any malfunctioning engine parts.