The P228(X) codes refer to the PCV or pressure control valve that is on the rail. The location of this PCV varies based on the truck. A LML PCV is on the front of the rail closest to the bump and a 6.7F PCV is on the back of the rail closest to the firewall.

This code means that the PCV is either sticking more open or closed when in operation and this can effect fuel rail pressure and driveability. While this code can typically be resolved by just replacing the PCV itself, it is overall recommended to replace the entirety of the driver’s side rail. The reasoning for this is that the seal between the PCV and rail is a metal to metal seal. If it does not seal properly the issues may be exacerbated.

The PCV must be extremely tight in order to seal and any leak will not show externally; the fuel will leak into the return port. It’s a good a idea to check the tightness of new OEM rails too.

A P0093 code is present when the truck notices that a downstream leak is present within the high pressure fuel system. There are many places for fuel to leak externally, but there are only two that can leak internally.

Internal fuel leaks are leaks that occur when the high pressure fuel is flowing to and through the return circuit when it otherwise should not be. This can occur due to excess return fuel flow from injectors or excess return from a PCV or relief valve.

The best ways to test for excess injector return is to perform an injector return test in the field or to send injectors into us for testing so that we are able to test the return flow. The best way to check for PCV or relief valve excess return is to ensure it is tighten down entirely and in some instances check return flow from the rail to see if there is return at cranking.

This code generally refers to the lack of rail pressure at cranking. A certain amount of pressure is commanded by the ECM and if that is not met (within reason), then the truck will not start. Likely culprits leading to this could be bad lift pump, excess return flow from the injectors or PCV, a bad HPFP, or a bad sensor.

A P0001 code is thrown when the truck notices that the Metering Unit/VCV/FCA is not receiving any signal. This can be due to it being unplugged, not fully seated, or a harness issue. This code means that the pump is running wide open as there is no current to tell it how open or closed it needs to be when in operation.

If fuel filter pressure switch switching frequency > 10, code is set – Indicates low supply pressure. Monitor fuel supply pressure from the lift pump (low pressure fuel system).

Ford’s error code description: “If the location of the gap on the crankshaft sensor wheel occurs at a location on the camshaft sensor wheel that is more than 6 degrees from the expected location for two detection attempts, the code is set.”

If this code is set, it is likely that the truck has a slipped crank gear. This can occur from excessive load on the engine such as aggressive aftermarket tuning.