I have read threads here about the ford engines blowing the plugs right out of the cylinder heads. I've noticed most people who have this problem are owners of 1998-2002. I haven't seen anyone who said they had an 2003. I have just bought a 2003 EB Expedition. Is this an issue I need to be concerned about? Did they correct the problem in 2003? I have the 5.4 Triton engine.

 

Sometime in the middle of 2003 production, they added some threads to the heads.
It is a problem, but just remember that for every one that has blown a plug, there are thousands out there that haven't. Most are caused by crossthreading or improper torque of the plugs. My 2001 has 52,000 on it with no plug problems.

 

I have also found that people who change the plugs when the motor is hot or warm are asking for trouble with these aluminum heads.

A buddy of mine blew a spark plug out of a 93 lincoln mark8 4.6 DOHC, and he changed the plugs when the motor was hot (bad idea).

The motor needs to be stone cold, I won't change plugs in anything unless it sits overnight.

Some people say the torque is a big deal, yeah I would use a torque wrench on them, but sometimes I just get them hand tight then turn it a quarter turn with the ratchet and call it done. I haven't had a problem yet.

Another reason the plugs are blowing out of the heads, I think the Air Conditioning tube is dripping condensation directly into the rear passanger side spark plug. I have seen this on several 5.4 SUV's, condensation dripping directly into where the spark plug is, it will rust out the threads on the spark plug, and that causes a blow out.

So I would just check the condition of the plugs, keep them changed, use anti seize, and keep an eye for condensation dripping anywhere.

JH

 

Mine did it at 47K and it is on the original plugs, the motor had not been touched other then normal oil and filter change's and up untill this point was trouble free! I guess I can no longer make that claim! I still don't think it should happen to a motor with only 47K on it and little if any hard towing!

 

Just went thru the same experience. My 2003 Expy with the 5.4 blew out one on the interstate. 51,000 on this SUV. Factory plug. It was one on the pass. side towards the firewall. $200 for a tow to a Ford Dealer, $100 for a room that nite , and $750 for a heli-coil. I don't know the production date of the vechile but will look into that. The comment above about a change in the threads mid-year is interesting.