Vehicle: 2011 Ford Crown
Victoria, V8-4.6L Flex Fuel
Problem: The vehicle was brought to the
shop because the engine would intermittently stall during various
driving conditions and the malfunction indicator light (MIL) was
Details: The technician connected a scan
tool and retrieved diagnostic trouble code (DTC) P018C – Fuel
Pressure Sensor B Circuit Low. He connected a fuel pressure gauge
to monitor the pressure. It was within specifications. At this
point, he called ALLDATA Tech-Assist.
The Tech-Assist consultant suggested monitoring the fuel rail
pressure sensor parameter Identification Data (PID) and compare
that to the actual pressure on the mechanical gauge to ensure the
correct fuel pressure values were being sent to the powertrain
control module (PCM).
The results of that test revealed that the fuel rail pressure
(FRP) sensor did not respond to changes in fuel pressure under
different conditions when compared to the mechanical fuel
pressure gauge readings.
Confirmed Repair: The technician replaced
the FRP sensor and retested the fuel pressure. This time the fuel
rail pressure sensor PID on the scan tool matched the mechanical
gauge fuel pressure readings. He cleared the DTC and test drove
the vehicle. The engine did not stall, and the MIL stayed off.