2001 F-150 5.4 ...it starts and idles good when cold but when warmed up it looses power and sounds like it's not firing on all cylinders...112,000 miles and I'm pretty sure it's running on the original plugs...does this sound like a plug issue?

 

At 112,000 miles it's due a plug change, and I would use Motorcraft plugs.

 

Yeah I need to change them anyway, but does this sound like a spark plug issue or something else?

 

Also, should I change the COP's while I'm at it?

 

Hard to say, but I would change the plugs first. Any codes?

 

No codes

 

Then buy a boot/spring kit for your COP's and reuse them. They are fairly expensive so I would see if plugs fix your issues first.

 

So I'm in the process of changing the spark plugs, and the ones I'm pulling out are autolite plugs...are these original plugs?

 

No. Motorcraft is original.

 

That's what I thought. I'm gonna go ahead and replace them with motorcraft though