I've been researching the spark plug blow out problem on the 5.4 engines. I can't get any real sense of what the statistics are showing about what year vehicles it occurs in, seems across the Ford line for the engine. I see a lot of Expys and F150s in this and other boards and the consumeraffairs website. There's even been a CPSC investigation done on whether or not the plug blowout can cause a fire, but the government says there was no evidence of it (although in many cases, it does tear up an engine, and the heads at the very least), and supposedly that TSB that Ford put out (07-21-2) details the 'approved' fix (and it ain't "Timesert").

All of this has got me concerned enough to just change the plugs now, at roughly 85k miles, rather than risk a chance of blow out. Ford claims those plugs were supposed to go 100k miles, but we all know (now) that interval is bull. Thing is, my engine has not exhibited any of the symptoms of blow out, like the ticking noise or misfires. What is weird to me is that a plug could actually 'rotate' freely enough under that COP to actually work itself up and out; you would think the COP had some amount of downward pressure to keep it from rotating, but maybe not.

Not to belabor the point, I'm just looking for advice on what appears now to be mandatory preventative maintenance (at a much earlier interval):
- If I change the plugs this week, should I just go ahead and change the COPS with those cheap Chinese-made versions you can get on Ebay for $100 for a set of 8? Or should I just get COP boots and replace those?
- I really can't tell if there is anything wrong with the existing COPS that I have now, is there some sort of ohm value I should check for?
- I've read about several methods of replacing the plugs; tool extensions, materials, etc. But after getting in there and really looking at the engine, it looks obvious to me that I'll need to remove the fuel rails: If I do remove them, do I need to have a set of injector o-rings on hand just in case? Can anybody tell me how to de-pressurize the fuel rail before 'pulling it out' of the head like the book says?
- If I take out the fuel rails, what else should I be doing to the injectors? I've had the engine serviced twice in it's life (about 40k intervals) to have the fuel system/injectors flushed by the dealer. I have read some of your posts that indicate even that procedure might not be good enough and that some of you have found tons of junk in the rails and injectors. What should I be doing with the injectors: pulling them out and soaking them in solvent and then cleaning them manually?
- For the plugs, what guarantee (other than torquing down the plug to spec) will I have that they won't break loose after I replace them? The whole plug thing seems like a material defect that is more related to a heat transfer differential issue (two different metals that heat and cool at different rates - aluminum/metal). Seems that if I just stick to OEM plugs and use thread dope and torque it down correctly, that I should be ok, but is has that been your experience when you replaced your plugs? Has that torque value actually been sufficient?

Any advice you have on the above and can share it would be welcome.

 

I have just a tad under 100K and have not had issues but will change the plugs here pretty quick. I will change the plugs, COPS, boots and I will be damn sure to use a torque wrench with inch/lbs and use antisieze on the plugs. i dont want to have to go back and do this again.

I plan on using OEM plugs and Motoblue COPs ( pretty cheap -<$30 ea and seem to have great reviews, even thought the company that sells them in the aftermarket seems to have poor customer service).

 

You do not have to remove the fuel rails, if you are not getting a miss why replace the cops? new boots might be a good idea look at the old ones for cracks,use antisieze on the threads not thread dope and torque plugs. I use a bead of di-electric grease around the top of boot just to help keep water out of the well, and a long plug socket is handy. It`s not as bad as it looks. If you do ever need to de-pressurize the fuel rail, pull the fuel pump fuse and crank the engine over, you need to do this before you change the fuel filter.

 

Yup, no need to remove the fuel rails. Removing them will make the job a bit easier, though, but I didn't pull them when I changed plugs on my old 00 5.4L EB.

I only used some antisieze on the threads of the plugs but that's about it. No dielectric grease, torque wrench etc. and drove over 2 years and 30+K miles without an incident before selling it a couple of months ago. Was I lucky, or did I just happen to do things the right way? Who knows...?

The spark plug blow out problem is definetely a concern, but sometimes it gets blown out (hehe... no pun intended...) of proportion. I don't think you should be so afraid of it that you'd refrain yourself from doing the plug change. Most of us don't have any problems whatsoever anyway.

Just take your time and make sure everything is right and you'll be fine.

 

You're right, I meant to say 'anti-sieze', I'll use that. Also, thanks for the procedure on depressurizing the fuel rail, hadn't thought of that method.

 

I agree, it does seem to be 'over-blown' in terms of an issue. I'll go for it and not worry so much. I'll probably replace the boots at a minimum, and just buy one spare COP to have on hand, that should be fine for now. Thanks for the help.

 

Any ideas or guidance on the fuel injectors (assuming I do end up pulling the fuel rails?) Thanks for your inputs so far.