There are new spark plugs you can get to replace the original ones.
Champion 7989, also there is a Motorcraft SP-515 alternative which is the new ford spec plug.
Also I believe in the US there are Brisk Racing plugs.

Just do a little research before you purchase to make sure you get the newer designed 1 piece plugs instead of the original 2-piece design which can foul up and break when you try to remove them leaving part or all of the end inside your head... Been there, done that

Just do a little research on em to make sure you get the right ones, don't leave it to your mechanic to pick them as not all mechanics are familiar with these engines and don't realise there is a newer design.


^^ One piece ^^

Hi all, I have a 2005 LTD, just spent the best part of last week removing and replacing spark plugs, yes all were seized, 145k, when I cleared the old plugs obviously some porcelain fell in the head, rigged up the vacuum with some clear hose and sucked out the debri, got the inspection camera in and couldn't see any debri on top of cylinders, changed oil for 0w/40 and bang she started no problem, sounded great, left it to warm up and took her for a gentle spin, then bang she started to make loud ticking and knocking noises, now the oil light comes on and beeps, can anyone confirm my worst fears and tell me she is cactus or if there is anything I can try to fix

Into the cylinder I assume??



It is possible that some porcelain got jammed either between the valve and seat, or valve and piston; or against the head. Because of this, the HLA (Hydraulic Lash Adjuster) may have been crushed in the rocker arm.

If it got jammed against the head, it may be a bent conrod



Reminiscent of a bent conrod/stuffed big end

Test for stuffed big end:

# start and run engine.

# rev engine; if knocking noise is "deep" in sound, and increases and decreases with revs, bad news. On light throttle openings, probably not a lot of "knock". Only becomes pronounced when engine is rev'd. Doesn't have to be rev'd hard.

Light tapping noise pretty constant through rev range = stuffed HLA.

Proper oil is 10W30 from new and then revised to 15W40 to reduce oil useage. I would put thicker oil in but would not think it should matter that much!