I have a 2003 F150 5.4L . I began to experience an interment shudder cruising at highway speeds that lasted for about 20 miles. After 20 miles the shuddering became contestant. Acceleration would make it worse.

connected scan tool and had sevral cop codes. After reading and asking around I replaced all fuel filter, 8 coils and plugs (MotorCraft).

Cleared codes and started engine.

Ran a bit rough then smoothed out. After about a minute I could feel a misfire then service engine light came on. A total of 5 codes P0354, P0355, P0356, P0358, P0304.

With the engine on I opened up live data and noticed both rear banks measured zero output voltage and fuel system 1 status switched back and fourth to OL TO OL FAULT.

Seems like after replacing everything I did the truck is in worse shape. I gapped the plugs to .54 btw.

no coolant leaks and no oil leaks.

 

First thing I would do is make sure you put the COP wires on in the correct order, and you didn't bend/break any connectors or pins.

 

I did break 2. And I didn't think it was possible to plug them in wrong. Only because they only reach to the nearest cop. But I will definitely double check and give an update.

 

If you broke 2, you have a problem with the connectors. Take them off, inspect both the COPs and the connectors. You may need to replace one or more connectors, hopefully you didn't also damage any COPs. Here is a set of pigtails that you can splice in:

 

I placed the order. Will arrive Sunday.
Thank You

 

I'm working on my 03 F150 5.4L
After replacing all the plugs, cop, fuel filter and the broken cop pigtails I still have a misfire.
I checked voltage on the cop with engine running and all but one measured 14v.
The wire that does have voltage connects to the side of cop that's printed B+.
Any suggestions?
And yes that is one of the pigtails I replaced. Did not use butt connectors. Sotter and shrink wrapped.
All parts except pigtails are Genuine Motorcraft parts.

 

back probe the wire before and after your repair FIRST. Then maybe back probe the connector. You just gotta trace it a little bit FIRST, then that will tell the tale if you have a problem or a minor issue.