hodo58 Report post Posted August 24, 2013 2005 Ford V-10 E-450 Chassis. I routinely get the Code PO 191 when acceleration to highway speed after a brief engine turn-off. The code indicates "Fuel Pressure Sensor Circuit Performance". The engine has no driveability issues. All service items are current. Scanning guage clears the code. Share this post Link to post Share on other sites
dickandlois Report post Posted August 24, 2013 hodo, Welcome to FMCA ! Possible causes: -High fuel pressure- Low fuel pressure- Damaged FRP sensor- Excessive resistance in the circuit- Low or no fuel- Wiring harness connector of the fuel pressure sensor- Fuel Rail Pressure Sensor- Vacuum leaks- Fuel http://engine-codes.com/p0191_ford.html#ixzz2cvUvsNW5 Rich. Share this post Link to post Share on other sites