Noticed today while driving that every time i stopped the car, the engine died and it would not tick over.
I changed the plugs when i got home from work in an attempt to cure this but once i restarted the engine it made a crazy clacking noise as it was being revved and definitely is not firing on all 6 cylinders. It did however tick over again

I replaced plugs with Denso PK22PR8 on the front and K22TMR11 at the rear.
Im guessing that the clacking is a tappet about to self destruct and the firing is maybe due to a duff plug or a lead not being connected properly.
Any other theories?