Has anyone else had a spark plug snap off on a 4.6 liter engine? If so, which plug was it? Had one do this Monday morning. A co-workers girlfriends F-150 did the same thing, same plug. Service Advisor stated that this was notorious with the 4.6.

 

Never heard of the 4.6 with the problem.

The 5.4 is famous for breaking the plugs. They are 2 piece ceramic plugs. The threads basically weld themselves to the heads over time.

It's random as to which would break. It wasn't a single cylinder issue, it was an overall issue.

 

Isn't it sad that Ford service writers can't even get their facts straight. You'd think they would - I'm sure they see several F150 spark plug jobs per week.