Ford's spark plugs on 4.6 and 5.4 engines from 1999 to 2003 have a design issue that make the spark plugs prone to blowing out. There are only four aluminum threads that hold the plugs in. The Ford dealers will want to replace the heads rather than repair them. Thin repair inserts may blow out again, so using a thick proven repair insert is recommended like the Calvan 389-100. Speed shops use them when modifying and rebuilding Ford 4.6 and 5.4 engines, the repair lasts the life of the engine. It could be a faulty plug or a vacuum leak that causes the cylinder to run far too lean. Replace a couple plugs, run it for a few miles (20 to 50) then pull the plugs and see what color they are. If the plug in the cylinder that failed is too bright, you're probably running lean from a vacuum leak. Unless you mean the plug simply came out of the head. If so, maybe it just got left loose and eventually worked it's way out. Also possible the threads are stripped out of the spark plug hole and the plug actually blew out. Take a look at the threads and see.
Screwed in the heads.
they are under the little circle black things which are called coils
.054 inch - according to motorcraft.com ( one of Fords websites )
That would depend on which engine size you have
sounds like the motor is running lean, not enough fuel.
To remove the fan shroud from the 1999 Ford F150 you need a user manual to guide you.
The head gasket is about to blow.....Typical ford..
There are a couple of a reasons why a 1994 Ford F150 truck will not start. The truck may have a dead battery or the spark plugs need to be replaced.
Removing the spare tire from a 1999 Ford F150 is simple. All you have to do is get under the truck and unbolt the spare tire.
i know if you have the 5.4L V8 you will have coil packs. not spark plugs
.044 inch
for what size of engine ?