Joined: Mar 2009
Location: Travis AFB / Fairfield
Read this thuroughly before attempting, and during if you need a reminder.
DO THIS WITH A COLD ENGINE! You will need a basic tool kit with 3/8 in. bits and a 3/8 in. ratchet with two 4 in. extensions, and also a flathead screw driver to remove your air intake housing. Make sure your new plugs are properly gapped. Make sure you have a bit to fit the new plugs, it will also be used to extract the old ones. I would not recommend new wires unless your old ones are shot or you are upgrading to a performance wireset. Now...
Lift the hood. Remove your air intake. This inludes the filter, MAF sensor, and all plastic bits up to the throttle body. Look on the side of the engine, just below the valve cover. There are three thick, likely black, wires running to the cylinder head. They are evenly spaced and have thicker "boots" where the wire meets the head. Pull on one of those boots, but ONLY ON THE THICK BOOT. Do NOT pull on the thinner wire part. You could break the wire if you tug on anything but the boot. Give it a good tug and it should come right off.
The plug is now exposed. Take your wrench, with the proper bit and number of extensions, and (lefty-loosy, righty-tighty) Take that old plug out. If it's stuck use some WD-40. Don't risk damaging your cylinder head in a "world's strongest man competition" with these things. Inspect the plug and compare it to the new ones. Cool, huh? Look for a chart on google images(search for "spark plug chart") and compare this plug to what plugs normally look like under certain conditions. When you're done, assuming there are no problems, tighten in a new plug (a little more than hand tight, but don't force it too much) and push that wire back on. It's that simple.
Also: Replace the plugs one at a time! If you take all of the wires off and then pull all of the plugs, you'll have a total disaster when trying to rewire.
Most of the plugs are simple to remove. A few are very, very tricky. At times it will seem hopeless, and you will feel like saying, "Screw this crap! It's worth $100!!!" But it simply isn't. The more you do things such as this the better you will become and the more naturally it will come to you.
When you're done, bump the engine over a few times. This means: crank it, but don't let it start. If it sounds normal, start it and wait a few seconds. If anything is a miss, shut it off quickly so it doesn't get too hot. Recheck all of your wires and make sure they're pushed tightly on there.
It should start without any issues, given you followed the directions well. Given this is the case, go for a well-deserved ride!
1995 5.0L GT, T-5, Black, 'vert.
1996 4.6L GT, T-45, Laser Red, 'vert.
1997 3.8L V6, 4R70W, Laser Red, coupé.
1997 3.8L V6, T-5, Black, coupé w/ sunroof.
1997 4.6L Cobra, T-45, Black, coupé.