I have a 2016 Silverado 1500 that code for a fuel rail pressure sensor-code p0191, have replace 3 of these sensors, and still the truck will go into reduce power mode, and turn on engine light, first two times sensors were replaced about 15k miles apart. 3rd time light came on with in 500 miles ?
Why not ask your Chevy dealer this question? Chevy has been replacing these under warranty, haven’t they?
These are the possible causes;
- Low or no fuel
- Faulty Rail Pressure (FRP) Sensor
- FRP harness is open or shorted
- FRP circuit poor electrical connection
- Faulty Fuel Pump
The sensor is but one reason the truck will throw this code, but your dealer should know this.
If you are running the fuel level really low often, stop it. That is one of the possible causes. I’d suggest refueling the moment the yellow low fuel light comes on.
If there is a fuel regulator, that can cause this code also.
Fuel pressure regulator isn’t on the fuel rail on this model . . . it’s part of the “fuel module”