allrighty so i bought a '98 expy 5.4 with 64k miles a week ago. i found out today that 2 weeks ago it blew a plug and was repaired at the dealer. now my question is what should i be worried its going to blow another?

its still on(as far as i know anyhow) factory plugs at this point and i wasnt planning on changing them till 100k.

i'm working on getting the paperwork to know exactly what happend and what was done to it. right now it runs great!

 

I have a 1999 F250 5.4L. Spark Plug blowout at 110000 miles in 2005. I now have 160000+ & no addl blowout problems. If it was repaired correctly, you should not have any additional problems from that particular cylinder. The other 7??? Keep your fingers crossed & the plugs properly torqued.

 

The guys over at blown out spark plug com helped me out with my blown out spark plug issues, I read on there F@Q page something about your question. Check out there web site for more info.

 

FYI, my 2000 5.4 blew #6. Yesterday I decided to check it out before taking it to the shop, and low and behold it took a new spark plug and it tightened down so it didn't strip the threads. I didn't find the old plug though, and the COP mount is broke and it's boot is cracked all the way. Today I'm going to replace the boot because it's missing badly at low RPM.

 

ok i got the print out today. it blew plug #3. they used a helicoil on it and new plug/coil. total cost was $413. it was on 7/22/10 with 63,713 miles. she now has 64,210 on her no odd noises or anything.

so the best thing to do is listen for the tick/knock type sound(which this truck had last year when i drove it) and make sure the plugs are TQ'd to specs randomly?

 

I'm usually in the E Series forums here but this topic naturally caught my attention------I'll share what I know or have learned hoping its somewhat helpful.

Ford advises using a nickel based anti-seize formula on the plug threads and of course carefully torquing them to the specs. I'm discovering so many of the so-called professional mechanics do NOT use the anti-seize and most don't pay too much attention to the torque either. Talking recently with my dealership about Ford's propriatary plug thread compound I was told nearly verbatim: "Hey man---my tech out in the shop says (screw) that (crap)---ya don't need it---they never use it!" Wow---tells me right there they won't be working on anything I own!

My '00 5.4 has 239K miles, I'm the third owner and so far its not had any issues with plug blowout. Recently replaced the existing plugs with a Motorcraft stock plug but added the Granatelli C-O-P set with a more consistent 25K volts---cost $200 for the complete set including boots and terminals. Dealer cost on just one C-O-P is about $80 I'm told, aftermarket I'm not sure the price each.

Honestly even if I bought a brand new Ford product first thing I'd change would be the plugs, making sure the proper anti-seize was in place. Its kinda sad after all this time the problem still exists.

HTH

J W

 

You better do at 50K miles instead 100K miles that where worse happened.

 

The reason most don't use anti-seize is it never mattered before. Ford screwed up on these heads and now we are stuck with doing things we shouldn't have to, to cover their mistake.

 

I'll admit that it seems as if Ford should have put additional threads in their modular V8 heads, but it is always good practice to use anti-seize and torque plugs to the proper spec. I have used anti-seize and torque wrenches for all plugs on the motorcycles, cars, and trucks I have owned since 1990 - no problems yet (and this has included 4.6 and 5.4 Ford V8s).

 

I too think even by now this plug problem could have been fixed in the head design but most likely it won't be--ever. Ford's suggestions and requirements might be the whole answer to it but following their recommendations can't hurt.

I've been using anti-seize on all plugs since a trusted mechanic suggested it---makes changing them much easier. With aluminum heads it only makes good sense to follow torque specs as well---its not like this hasn't been a common practice anyway.

Another issue is removal of plugs at the 100k interval---factory recommendations as well as numerous hands-on experiences suggest something like PB Blaster or Kroil be used to loosen and dissolve any thing that might damage or affect threads in the head. Its possible skipping this step contributes to spitting plugs out after replacement. Again it can't hurt---especially at 100K miles if they've gone that long.

I also agree changing the plugs at about 50K is smart---most of the issues I've read about or over heard all had to do with those left until 100K. I'm just not convinced any spark plug will run 100K well enough to justify leaving them in that long.