what direction to take?

[black_demon69]

3 re curing codes (it does take a little time to set them again)
P0300 FORD - Random Misfire Detected
P0303 FORD - Cylinder 3 Misfire Detected
P0330 FORD - Knock Sensor 2 Circuit Bank 2

truck is a 2005 f250 with the 5.4l 242,000miles
symptoms:
CEL starts blinking and it starts missing and has loss of power @around 45 to 65 mph smooths out after that
CEL stops blinking a few seconds after gas pedal is released.
seems to idle fine

fuel pressure w new fuel filter as reported by scanner is around 40 to 45 psi
previous owner has replaced
spark plugs
coil packs
injectors
ECU
air filter
knock sensors

Yes he was throwing parts @ it and I don't know what kind of trouble shooting if any he did..

I plan on checking compression and possibly doing a cylinder hold test also smoking the intake to look for Vac leaks..


some guidance would be nice and appreciated

 

[Dirtman]

Fuel pressure is too low, but I would check it with a guage not a scanner. Should be 65psi. Usually that would set a lean code but it's definitely somewhere to start.

If the knock sensor was replaced I'd verify the wiring and connection. But running lean can cause the knock sensor to throw a code (back to that low fuel pressure).

And running lean can cause misfires (low fuel pressure again).... so I'd be looking at the fuel pump or module.

 

[black_demon69]

It popped up another code in addition to the ones
P0316 FORD - Misfire Detected On Startup First 1000 Revolutions

Read more: https://www.autocodes.com/p0316_ford.html

 

[black_demon69]

Fuel pressure checked and is low I have ordered a fuel pump I will update when I get it in

 

[Dirtman]

Hope you bought a Ford pump.

 

[black_demon69]

Carter pump

 

[black_demon69]

Fuel pressure is better with new pump but symptoms are still the same and codes remain.

It was the original fuel pump and there were some metal shavings in the bottom of the fuel pump assembly