motorhead6

Since I bought my 2005 f150 5.4 liter. It has had a knock when it came close to oil change time that was at 38,000 miles. I now have 66,000 and the phasers knock is loud as can be with new or old oil. I am also getting performance issue. I have a noticeable miss at idle when the truck is at operating temp. Every once in a while the truck shifts up to over drive it will start bucking like crazy then goes away after a few minutes. Just this week while getting onto the interstate the trucks rpms started jumping from 500 to 3000 and the check engine light was flashing. no codes where thrown, but the truck nearly died and could not get out of its own way. The only code I have ever gotten was p0316 for miss within the first 1000 rpms. I have recently change the spark plugs. When the engine is missing I have removed all eight cops one at a time to see how it effected the miss. The usual miss is completely different from a unplugged cops. So, are the phasers whats causing the miss? I was thinking crankshaft position sensor but a mechanic friend of mine said that was doubtful. Can the phasers cause these performance problems or just noise? And if the phasers are bad and I have to go that deep into the engine what performance pieces are out there. I have found a bunch of cams but would rather replace the heads. Does anyone make performance heads for these engines or am I stuck with a port and polish job.

Tyler6.0Powerstroke

If it was my truck giving me those issues I would say it was either the spark plugs or one spark plug, or the cop's. What kind of plugs did you use when you just changed them recently?

vintageman

Also, how did you torque your plugs down, with a torque wrench or just with the socket wrench? Loose plugs can cause a noise as well.