Bought a 2006 Expedition with 5.4 3V back in the spring. Currently has 131,000 miles. Experienced some bucking and hesitation issues when the weather was still cold. Assumed that I would eventually need to replace some coil packs and/or spark plugs.

The weather warmed up and it ran really well all summer.

The other night, the weather is cooler again, it started running really rough, wife reported especially at low RPM. She had just put some gas in it that evening. It gets limped home.

I get to checking into it today. Oil was super low, topped that up. Rough idle comes and goes every minute or two. Idling up doesn't seem to make a huge difference. A bunch of codes come up repeatedly: Fuel too lean on bank one; Cam timing advanced on bank one; O2 sensor reading too rich on bank two; cam retarded on bank two; Multiple/random misfires; specific misfires usually on 5, 7, and 8.

Some research points to the variable timing control solenoids, maybe. Also, likely to need fresh plugs and maybe some coils. No idea whether the first owner ever replaced the factory ones or not. Tempted to take it to the mechanic for full oil/filter, spark plugs, and have him actually test the coils while they are off. Wanted to get some input first.

 

Sounds like you either have a large vacuum leak of the fuel pump is weak and not delivering enough fuel pressure.

 

What pressure should I be seeing on the fuel rails? My OBD tool will display it in real time data, but I don't know what range it should be in.

 

Additional information:

So I noticed tonight that when the engine is running rough, the scan tool reads that the fuel system is in Open Loop, shows OL-fault; and when it smooths out, it shows closed loop, CL.

 

 

KOEO 35-45 PSI
KOER 28-45 PSI