I have read many threads on this problem (blown plugs) but have not found any agreement on when Ford actually fixed this problem. When did Ford fix the spark plug blowing problem? I have heard 2000, 2001 and 2003. Which is it? Did they go to a plug with more threads?

Thanks

 

2004 for sure. Have you seen the plugs for these new 3 valve motors? The have about an inch of threads on them. I hope it was 2001 so mine will be ok!!!
Jimmy

 

The actually production date of the improved heads was late 2002 models and all 2003 models up.
BUT all the new heads you buy from ford have the longer threads

 

Great! That means my 2003 should be safe!

 

Ok, so if you want to prevent this from happening again and you own a ford previous to 2002 would you have to buy new heads or just the coil packs that they put in are longer? if you have to buy the new heads any idea how much they are?

 

The coil packs aren't going to hold the plugs in with the compression in the cylinders trying to push them out!!
Jimmy

 

A little tougher question -- If the switch to the improved head was made in 2002, was production/sequence number or build date was the change made?

Thanks in advance from a concerned '02 owner.

 

I heard November 14 2002 was the switch day. If you have a 2003 1/2 you should have the improved design. Look on your passenger side head between cylinder 2 and 3, there's a date and time printed in ink on the aluminum head. The new heads should have 8 threads instead of the 4 on the older designs.

 

v10Mustang:

Hmmmm.....i ordered my 2002 truck in November 2001 and it was delivered December 2001. Does my 5.4 have the 'short thread' design?

And does a 'short thread' owner have to just sit back and wait for a plug to blow, or is there some type of preventative maintenance that can be performed? I have an extended warranty on my truck up to 72,000 miles. I'm at 34,000 miles currently, and so far my 5.4 runs great....does anyone have some wood i can knock on????

-hooD

 

I bought mine in late Feb 2003. How do you see this date code? I can seen no way of looking at the head short of removing it. The inside is covered with intake and the outside is crammed against the fender well.

 

The date code is a lot harder to see on a 4WD F150 because you don't have the coil cutout in the wheel aprons, but you could look at the date code of your engine. (it's on a white sticker on the driver's side valve cover near the oil dipstick.) The heads are usually made within a few day's time of the engine block. My heads say 05/01/03 while the engine says 05/02/03.