Can someone please provide me with some quality information on "Spark Plug Blow Out" on the 5.4L engines used in Lightnings, F150s and Navigators. I have a Navigator that just lost a spark plug under normal driving at 40 mph. Does the head or heads have to be replace after this occurs? Is this common for the Navigators? I've never lost a plug before until today. Thanks.


I need the experts advice here.

 

It's a fairly commom problem on the mod motors. The heads on the earlier ones only have a few threads in the head. try a search there's a ton of info:







just click the buttons and try it out...JR

 

Shouldn't this be covered by Ford Motor Company?

 

Are you still with in the warenty?

Suavy

 

What year Navigator ? Only the 98 Navigator had a 2 valve motor, 4 valve motors dont experience this problem. Furthmore this problem is Isolated to PI Heads which I believe didnt come out unil 99. Hope this helps and yes if your under warranty Ford will cover it.

 

you should be able to fight it without a warranty.i blew a plug on my 2000 lightning.a few years ago my brother blew a plug on his 99 f-150.neither of us had warranties.both vehicles were purchased used. after the vehicles we in the shop we filled out complaint forms (cant exactly remember what ford calls them).we got them from the service manager.filled them out and returned them to the service manager.they contact ford about the complaint.we each got the same responce. ford replaces the head and threw on a 1 year warranty and we had to pay $500.00.this happened about 2 years apart.the whole time ford denied this is a problem