JFitz

I've owned the car since 83,xxx. I don't know if/when the previous owner changed the spark plugs, but I've been changing everything else I can just so I know when it was done. Filters, diff fluid, radiator flush, etc. Then I find out about the spark plugs.

Am I just screwed when it comes to changing them? The engine runs beautifully, but the head design thing is scaring me.

What do you guys think? Is this a job for my mechanic? (Not my dealer, I don't like/trust my local dealership and don't know of any good ones in the Dallas area.) Or should I just attempt it myself? I've seen lots of guys kinda of freaking out about changes at 25K+ so at 85K...

moosestang

Grip it and rip it! Seriously, it's not that complicated. i set my torque wrench to 25 ftlbs and give it three pulls till it clicks, then I pull till it breaks free.

If it runs good, then I'd probably leave it be. Might as well wait 15k more miles or till it starts performing poorly.

JFitz

So, as long as I follow the precautions I've seen people using (warm-up engine, torque wrench, etc. ) I should be fine? Is there a specific plug that helps/eliminates this issue that I can replace it with? If I have to shell out a bit more for a plug that will prevent a more expensive repair, I'm fine with that.

moosestang

People buy the champion plugs, but I would just replace with motorcraft or autolite.

I've never warmed up the engine or soaked the plugs in anything, but I've never had 85k miles on a set of plugs.

Roush05

I changed mine out while changing out the cams. I actually did it on a cool engine. I got the initial turn going, and then sprayed PB Blaster down around the threads and let them sit until I had the cam on that side swapped out, and then I went back to them and they all backed out easily.

Exley

I did mine at about the same mileage with success. I was terrified too!

I did mine with a warm engine, though Ford and others on the forum do NOT recommend this because of the risk of hurting the threads. Took all the coils off and sprayed PB blaster down each spark plug hole. I waited 5-10 mins and broke each plug loose, started with the first plug again and worked them each loose. If you use this method make sure you crank the engine with the plugs out to clear the PB blaster from the combustion chamber.

Good luck!

Here is the link to my thread when I pulled mine. https://mustangforums.com/forum/4-6l...other-day.html

EDIT: also, about taking it to a mechanic, I would recommend doing it yourself if you are mechanically inclined. I would be concerned that a mechanic would be over confident about a plug change and might rush it and break one. On the flip side, when i bought the plugs at autozone the guy hoped god had mercy on my soul :-P so I think it is a well known problem. His experience was with an F150 truck i think