Installed incorrectly with improper torque. Or possibly the threads were ruined by someone cross threading the spark plug. Ford has problems with the design of this aluminum cylinder head, though they do not acknowledge it. Just search Google and you will see many cases where the spark plugs have ejected (even the original spark plugs that were installed during assembly) at very low miles. For more information on a money saving kit that allows the repair, not replacement of the cylinder head search DenLors 38900.
Does a 2003 ford expedition have spark plugs?
It has spark plugs. They are just hidden from view.
Yes , it has 8 spark plugs
6 spark plugs
the best spark plugs for all ford vehicles are the motorcraft type, which they come from ford.
( 8 ) spark plugs
There are ( 6 ) spark plugs
How to replace spark plugs on a 2010 ford fusion
( 6 spark plugs ) with the V6 engine ( 8 spark plugs ) with a V8 engine
ford engine 5.4/8cyl located where are spark plugs to bi install
Where and how do you find the spark plugs for a 1997 ford expedition?
8 spark plugs