'98 Expedition spark plugs

[DCDodge]

Anyone have any advice to make changing the spark plugs on my '98 Expedition any easier than it appears it is going to be? Looks to be quite a job. I have the 4.6L. Check engine light keeps coming back on and the code is for #1 misfire, so obviously it's time to change the plugs.
Any helpful tips would be greatly appreciated.

[iarobj]

I have a '98 5.4 Expe coming up on 100k. I spoke with a few mechanics and they all said that changing the plugs is a bit of a task. I still plan on doing it myself, I will let you know how it went.

[dxrflyboy]

It's not too bad of a job, except for the #4, since the heater hoses and electrical components are in the way. You will need several different length extensions. I use wobbly end extensions and have to "piece" them together to get down the #4 hole. Use a regular 5/8" deep socket when installing the new plugs to prevent the socket from coming off your extension down in the hole.

[iarobj]

Thanks for the tip, I still haven't completed mine yet. I have a number of other things to fix like the heater and a/c. Looks like I will have a good excuse to buy more tools. Cool!!!

Originally Posted by dxrflyboy

It's not too bad of a job, except for the #4, since the heater hoses and electrical components are in the way. You will need several different length extensions. I use wobbly end extensions and have to "piece" them together to get down the #4 hole. Use a regular 5/8" deep socket when installing the new plugs to prevent the socket from coming off your extension down in the hole.

[DCDodge]

Well, I'm getting ready to tackle it in the next couple of days. Thanks for the tip, I'll let you guys know how things go.

[amac209]

i'm willing to bet a beer that the misfire is caused by the coil. carefully check for cracks and carbon tracking. another tip for changing spark plugs in any engine is to blow compressed air around the plug before removing it. also the plugs should be properly torqued. there's been many cases of plugs blowing out of ford aluminum heads.

[dxrflyboy]

True about the coil and plugs blowing out. I've learned to change the coil and the plug in the event of failure, since coils often fail due to a misfiring plug and the plug fouls due to a faulty coil. Use dielectric grease on the plug boots. 5.4L engines have always been coil on plug, but the 4.6L had wires until 1999. I could be wrong on the changeover year, though.

[DCDodge]

Hey,guys, thanks for all the tips. I have a couple of new concerns. In reference to the aluminum heads, I heard that anti-seize should be applied to the plug threads prior to installation so they won't melt to the heads...true? Also, should the truck sit overnight and be as cool as it can get before changing the plugs?

[dxrflyboy]

Cooler is better when changing plugs. As far as the anti-seize goes, I tend to put it on everything, but one of my coworkers at my last job was dead set against using it on plug threads in Ford OHC V8s. Supposedly, what happens is that the plugs vibrate loose, then wipe out the threads. Once this happens, the plug blows out of the head. OTOH, the anti-seize ensures a correctly torqued plug that is fully seated. Installing the plugs "dry" allows excessive friction to give the false impression that the plug is tight before it seats fully.

[DCDodge]

I think I'll still go with the anti-seize. I've heard this from too many people to risk not using it now.