I have a 2010 STX with the 3v 4.6 with 140k on it. I bought it with 134k and changed the oil as soon as i bought it. I used a fram filter and castrol gtx oil. At idol it sounds kind of like a diesel. Has anyone experienced this and dug in to it? If so what was your conclusions/results? Or has anyone heard of it? Thank you in advance for any input.

 

The noise is coming from the variable cam timing. Somewhat typical and sometimes fatal to the engine. Others who know much more than I about this issue will chime in and they will also tell you to ditch the Fram filter.

 

Thank you, I have read to use an oem filter which I'm gonna do when I change it again in a couple weeks.

 

The cam phasers have already been changed and that did not change the issue

 

The oil screens on the solenoids may be plugged. Engine may have sludge if it wasn't maintained well. You may need chains and tensioners.

What weight oil did you use? Definitely get that Fram off of there.

 

The solenoids were also changed, as far as oil i used 5w20 or 5w40. I don't remember lol. Which i know sounds bad lol.

 

Well, 5W20 is what Ford recommends, but some people say that heavier oil will quiet it down.

Low oil pressure due to wear can do this too, some people replace the oil pump with a high capacity one when they change the chains and tensioners.

 

If you can, try to determine where the noise is coming from. Front, right, left..... Have seen numerous times on these engines where the timing chain guides have worn. Some due to chain tensioner failure. Good luck.