I have a 2001 f150 5.4 and just started getting a slapping, knocking or ticking noise. It doesn't matter if it could or hot it gets louder as rpms increase. Its coming from the drivers side valve cover I can actually feel it when i put my hands on it. Any ideas are greatly appreciated i believe it is to old for cam phaser

 

anyone?

 

Are you absolutely positive it's not an exhaust leak? Also, the sparkplugs are notorious for getting loose in that year, you better make sure one is not baking out. If it does back out it will blow, taking threads with it. Plugs should be torqued to 28 ft lbs.