Yesterday I finished the dreaded SP-505 plug change in my 2005 FX4 at 178,994 miles. I kept putting it off because of all that I have read about how bad this can be. For the last 2 years I have been running 91/93 octane and Techron fuel cleaner religiously to keep the carbon level in check. I was still getting 14 mpg in town and 17 mpg on the highway. I used 3/8" impact without any penetrating or carb cleaner and had zero issues on the front 2 on each side. The back 4 took more patience. The drivers side rear came half way out and then froze and wouldn't go back in or further out with the impact max'ed out at 100 ft lb. I gave it a good PB blaster spray and let it sit 15 min and out it came. The passenger side rear I did a preemptive spray and it took about 15 seconds on the impact before it started to rotate.

Anyways, all have been replaced by SP-515s and truck is running great and no fault codes. And I can now buy 87 octane gas again.

Here are pics of the plugs.

 

Congrats! This proves miracles do happen

 

Yeah I bought the extractor tool but being superstitious I refused to take it to the garage. LOL

 

Glad to hear something good about the 5.4 3V spark plug change instead of another horror story.

 

It's the Techron that does the trick.. I ran about 3 bottle through mine, helps them come out like butter.. Congrats!

 

Good job! You did it correctly.

 

After looking closer at you're plugs they look different then the ones I pulled from my 07' I changed mine at 150k since the original owner couldn't give me a definite answer whether they did them or not. You had much better luck then me...lol. I broke 7 of 8

 

Yes your plugs out of the 2007 are different and they look a lot more like the SP515s. The main thing with this job is use the Techron religiously for a good amount of time and when you're doing the plugs use an impact and be patient. Don't do anything rash and take your time.

 

I can't wait to put 87 octane in the truck later this week. I'm trying to remember who was president then. LOL

 

I think you're regular use of techron definitely helped. I only ran three tanks of techron and I started off using a 3/8 cordless impact but they just kept breaking. So I did the rest by hand. That's the thing with this job...it can go real good or really bad.

 

Yes I have noticed that it usually goes pretty well or it's a total disaster. I used the techron for almost 30k miles. I have to believe that made some difference.

 

Just did mine not too long ago at 151k on a 5.4 3v. After a ton of research before this job, I came to the conclusion that using an impact is the way to go. Normally, I wouldn't do this, but from all the posts I've read, using an impact yielded the best results.

I ran seafoam for a couple of gas tanks leading up to the change. I broke them all loose 1/4 turn for most, some only 1/8 as they were tough. I then poured some Seafoam deep creep into each plug hole. The Deep Creep did make it down to the shields on most of the plugs. Filled them just past the plug's nut. I let it sit for an hour while I changed the plugs on my old 4.6 2v (cake walk). I used a 3/8 impact for all but the two back ones (couldn't reach with impact) to extract. It was certainly dreadful to extract those rear ones by hand. They were tight and screeched the whole way. I ended up breaking #1 cylinder's plug. If one were to break, I was sure glad it was the easiest to access. Strangely, it was the easiest to break loose and once I got it out, it was the cleanest! There was barely any carbon on it compared to the others! Thoughts?

 

For the rear passenger plug I pulled the ecm and support bracket which created a gigantic amount of space. I used a regular 3/8 universal joint with the impact only because the plugs turn very slowly so I figured there wouldn't be an issue with it flipping around and breaking or damaging something. For the drivers side rear i removed the screws for the valve that sits on the firewall and pulled the rubber hose loose which created enough space for me to stick my 3/8 Campell Hausfield impact down in there. now it was a lot of trial and error getting the right combo of extensions. on that plug it behaved strangely in that half way out it froze and wouldn't go either way. PB blaster and several soaks and a ton of time getting hit by the impact finally made it come out. For your #1 plug being so clean and breaking I have to think it was just not made correctly. I took the front 2 on both sides out dry with an impact and no carb cleaner or penetrant.

 

After 300 miles of driving with new plugs I am getting a rough idle during warm up. It starts with the temp gauge is just below the first tick mark on the coolant temp gauge and goes away just before it gets to operating temp. It does not do it at cold start up nor fully warmed up. Once warmed up though I can tell there is a little bit of uneasiness in the idle. I am going to inspect all the coil boots and springs this weekend to make sure i have everything seated well. I hope it isn't a coil going bad.

 

Have you ever cleaned the throttle body and MAF?