I would like to do a spark plug change. However, it looks pretty scary. Has anyone done this on the 5.4? Any tips on DIY?

 

It's not hard, just time consuming. Have the right tools, extensions, 1/4" sockets all sizes and universal elbows. I use electrical tape to hold sockets, elbows, and extensions in place, you don't want to lose tools. Be careful unplugging the FI and COP connectors, get some thick padding so you can lay over the engine. Before you remove the plug, use an air hose to blow debris out of the plug well. Use anti-seize on the plug threads and dielectric grease in the plug boots during installation. Clean the plug well as best you can. Don't remove the fuel rails, but there are some other things (pwr steering fluid res bracket, intake shroud) to remove to make it easier.
Good luck! You'll be glad you did it!

 

In short, it's a detailed job that took me a while to do it (a couple days) the first time through. I learned and took my time and can conclude that the job is not impossible; it requires patience and prep work.

First things first, I have done this job twice. If you are short, I recommend removing the front wheels and placing the front crossmember on blocks. Although I am 6'3", I did this the second time and found it to be easier to access the back plugs. Secondly, you need to do disconnect the battery (neg batt terminal) and the three power wires (in red) on the firewall. Then, disconnect that entire assembly of wires and plastic connectors from the firewall. It has four bolts total to remove it. By removing this, you are giving yourself more working room for accessing the plugs.

Then remove the air cleaner assembly all the way to the throttle body and remove the triangular bracket nest to the power steering reservoir. This will give you the most working room as possible.

Before tackling the plugs, I recommend spraying penetrating oil down all of the plug wells and letting it sit over night. This was recommended to me by another member and I agree after doing this job.

As mentioned, use tape to hold your extensions and swivels together. Remove the rubber o-ring from your plug socket and remove plugs by loosening them then extracting them with a magnet. Upon reinstallation of the plugs, use a 6-8 inch section of 3/8 ID fuel line to start threading your plugs first. Once threaded in, remove the fuel line by pulling up and torque your plugs to 12 ft lbs. Also, use a liberal amount of anti-seize on the plugs. I also used Motorcraft plugs.

If you haven't thought of this, I also recommend installing new coil packs. I bought mine from Global Automotive on Ebay and have had no problems in 12k miles. Use dielectric grease on all tips of the coil springs and boots to keep corrosion away and seal moisture out.

Remember: take your time!

PS - here's my old thread when I first did my plugs: https://www.ford-trucks.com/forums/8...-question.html

 

Most importantly, MAKE SURE YOU USE A PROPERLY CALIBRATED TORQUE WRENCH AND ACTUALLY TORQUE TO SPEC! These motors are notorious for stripping out the plug threads because people just german torque in the spark plugs or gorilla them in crossthreaded. If you do it right, take your time and make sure to do the change on a dead cold engine that has sat overnight, you should be fine. A lot of these newer motors are a complete pain to do the plugs but DIY beats paying a ridiculous amount for a shop to do a job that used to take an hour on older vehicles. I can do my Cobra in 30 minutes lol.