Bad tapping noise

[Geary]

2002 XLT Expedition here with 117,000 miles. Tappet like knocking noise. It's a really bad "metallic" sound coming from the passenger side top end of the 4.6L. Two mechanics have told me it could be anything from a 1300 dollar to 6000 dollar fix (the large number for a new engine). It sounded like something bad on one of the pulley objects but when we took the belt off...the sound was still there. It will drive but misses like mad after warming up just like when I had to replace 2 C.O.P.s before. But, it idles medium and revs up to 4 grand as smooth as silk. They want 350 bucks just to take the top of the engine apart to "see" what's going on. They say it could be a bad valve train, tappets, valves, or timing chains. Anybody here have a similar thing and what was the fix?

 

[bcmaxx]

2002 XLT Expedition here with 117,000 miles. Tappet like knocking noise. It's a really bad "metallic" sound coming from the passenger side top end of the 4.6L. Two mechanics have told me it could be anything from a 1300 dollar to 6000 dollar fix (the large number for a new engine). It sounded like something bad on one of the pulley objects but when we took the belt off...the sound was still there. It will drive but misses like mad after warming up just like when I had to replace 2 C.O.P.s before. But, it idles medium and revs up to 4 grand as smooth as silk. They want 350 bucks just to take the top of the engine apart to "see" what's going on. They say it could be a bad valve train, tappets, valves, or timing chains. Anybody here have a similar thing and what was the fix?

I have a similar tapping/rattle sound from top of pass front of engine, It comes and goes . But no miss. Still waiting to find out what it is, or something to let loose