Hi all..new member here. I tried searching the forums with no results. Truck has 129,000 miles.

Last week I changed both fuel filters and now I'm getting a P0087 error code. The display is showing the Reduced Engine Power check engine light as well. The code is low fuel pressure and it won't go above 65 mph.

The truck is deleted so Forx dealerships are no help. Could this be a result of the fuel filter install? Maybe I didn't clear the air from the line correctly? It ran great for 3 days before this error. No issues before that either. I have the live wire tuner with shift on the fly. Anything else that could be causing it?

 

Your code P0087 is a low rail pressure code. This is on the high side. If there is no message on the dash for low lift pump pressure, then you have an issues with the high pressure side. Hopefully it is not a CP4 pump issue. Air is bad for that high pressure pump.

Did you use motorcraft filters? Are you sure the installation was done correctly?
Primary filter cap all the way on (ie no gap at the bottom of the cap)? What did you do to purge the air out after the filter change?
Verify you have 55 psi on the hose coming back to the secondary fuel filter.
Verify volume coming out of the secondary fuel filter. 1 liter minimum in 30 seconds.

Is the high pressure pump noisy?

 

Hi. Thanks for responding...
Yes, pump is very noisy. How do I verify psi and fuel delivery? Yep, motorcraft filters. The cap was all the way in with filter seated correctly (I think).

To purge the air, I cycled the key on, waited 30 seconds, then cycled it off. I did that 6 times.

 

IIRC there was a youtube video talking about the fuel flow and pressure testing. I'll try to find it.

You measure the flow by turning the key on with the pump discharge hose disconnected and directed to a container.
You need a manual pressure gauge to verify the pressure.

 

I would try forscan to get more data to find out what’s going on. Also try live data of fuel line pressure and fuel pump pressure and try ohms test on injectors so they are in range for a more accurate reading. Google ohms on your injectors.
Good luck